docs: refresh and correct stale documentation across repo (#306)

* docs: refresh and correct stale documentation across repo

Walked the README and docs/ tree against current code and fixed several
real bugs and many stale references. Highlights:

User-facing
- README.md: web interface install instructions referenced
  install_web_service.sh at the repo root, but it actually lives at
  scripts/install/install_web_service.sh.
- docs/GETTING_STARTED.md: every web UI port reference said 5050, but
  the real server in web_interface/start.py:123 binds 5000. Same bug
  was duplicated in docs/TROUBLESHOOTING.md (17 occurrences). Fixed
  both.
- docs/GETTING_STARTED.md: rewrote tab-by-tab instructions. The doc
  referenced "Plugin Store", "Plugin Management", "Sports Configuration",
  "Durations", and "Font Management" tabs - none of which exist. Real
  tabs (verified in web_interface/templates/v3/base.html) are: Overview,
  General, WiFi, Schedule, Display, Config Editor, Fonts, Logs, Cache,
  Operation History, Plugin Manager (+ per-plugin tabs).
- docs/GETTING_STARTED.md: removed references to a "Test Display"
  button (doesn't exist) and "Show Now" / "Stop" plugin buttons. Real
  controls are "Run On-Demand" / "Stop On-Demand" inside each plugin's
  tab (partials/plugin_config.html:792).
- docs/TROUBLESHOOTING.md: removed dead reference to
  troubleshoot_weather.sh (doesn't exist anywhere in the repo); weather
  is now a plugin in ledmatrix-plugins.

Developer-facing
- docs/PLUGIN_API_REFERENCE.md: documented draw_image() doesn't exist
  on DisplayManager. Real plugins paste onto display_manager.image
  directly (verified in src/base_classes/{baseball,basketball,football,
  hockey}.py). Replaced with the canonical pattern.
- docs/PLUGIN_API_REFERENCE.md: documented cache_manager.delete() doesn't
  exist. Real method is clear_cache(key=None). Updated the section.
- docs/PLUGIN_API_REFERENCE.md: added 10 missing BasePlugin methods that
  the doc never mentioned: dynamic-duration hooks, live-priority hooks,
  and the full Vegas-mode interface.
- docs/PLUGIN_DEVELOPMENT_GUIDE.md: same draw_image fix.
- docs/DEVELOPMENT.md: corrected the "Plugin Submodules" section. Plugins
  are NOT git submodules - .gitmodules only contains
  rpi-rgb-led-matrix-master. Plugins are installed at runtime into the
  plugins directory configured by plugin_system.plugins_directory
  (default plugin-repos/). Both internal links in this doc were also
  broken (missing relative path adjustment).
- docs/HOW_TO_RUN_TESTS.md: removed pytest-timeout from install line
  (not in requirements.txt) and corrected the test/integration/ path
  (real integration tests are at test/web_interface/integration/).
  Replaced the fictional file structure diagram with the real one.
- docs/EMULATOR_SETUP_GUIDE.md: clone URL was a placeholder; default
  pixel_size was documented as 16 but emulator_config.json ships with 5.

Index
- docs/README.md: rewrote. Old index claimed "16-17 files after
  consolidation" but docs/ actually has 38 .md files. Four were missing
  from the index entirely (CONFIG_DEBUGGING, DEV_PREVIEW,
  PLUGIN_ERROR_HANDLING, STARLARK_APPS_GUIDE). Trimmed the navel-gazing
  consolidation/statistics sections.

Out of scope but worth flagging:
- src/plugin_system/resource_monitor.py:343 and src/common/api_helper.py:287
  call cache_manager.delete(key) but no such method exists on
  CacheManager. Both call sites would AttributeError at runtime if hit.
  Not fixed in this docs PR - either add a delete() shim or convert
  callers to clear_cache().

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix WEB_INTERFACE_GUIDE and WIFI_NETWORK_SETUP

WEB_INTERFACE_GUIDE.md
- Web UI port: 5050 -> 5000 (4 occurrences)
- Tab list was almost entirely fictional. Documented tabs:
  General Settings, Display Settings, Durations, Sports Configuration,
  Plugin Management, Plugin Store, Font Management. None of these
  exist. Real tabs (verified in web_interface/templates/v3/base.html:
  935-1000): Overview, General, WiFi, Schedule, Display, Config Editor,
  Fonts, Logs, Cache, Operation History, plus Plugin Manager and
  per-plugin tabs in the second nav row. Rewrote the navigation
  section, the General/Display/Plugin sections, and the Common Tasks
  walkthroughs to match.
- Quick Actions list referenced "Test Display" button (doesn't exist).
  Replaced with the real button list verified in
  partials/overview.html:88-152: Start/Stop Display, Restart Display
  Service, Restart Web Service, Update Code, Reboot, Shutdown.
- API endpoints used /api/* paths. The api_v3 blueprint mounts at
  /api/v3 (web_interface/app.py:144), so the real paths are
  /api/v3/config/main, /api/v3/system/status, etc. Fixed.
- Removed bogus "Sports Configuration tab" walkthrough; sports
  favorites live inside each scoreboard plugin's own tab now.
- Plugin directory listed as /plugins/. Real default is plugin-repos/
  (verified in config/config.template.json:130 and
  display_controller.py:132); plugins/ is a fallback.
- Removed "Swipe navigation between tabs" mobile claim (not implemented).

WIFI_NETWORK_SETUP.md
- 21 occurrences of port 5050 -> 5000.
- All /api/wifi/* curl examples used the wrong path. The real wifi
  API routes are at /api/v3/wifi/* (api_v3.py:6367-6609). Fixed.
- ap_password default was documented as "" (empty/open network) but
  config/wifi_config.json ships with "ledmatrix123". Updated the
  Quick Start, Configuration table, AP Mode Settings section, and
  Security Recommendations to match. Also clarified that setting
  ap_password to "" is the way to make it an open network.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix ADVANCED_FEATURES and REST_API_REFERENCE

REST_API_REFERENCE.md
- Wrong path: /fonts/delete/<font_family> -> /fonts/<font_family>
  (verified the real DELETE route in
  web_interface/blueprints/api_v3.py).
- Diffed the documented routes against the real api_v3 blueprint
  (92 routes vs the 71 documented). Added missing sections:
  - Error tracking (/errors/summary, /errors/plugin/<id>, /errors/clear)
  - Health (/health)
  - Schedule dim/power (/config/dim-schedule GET/POST)
  - Plugin-specific endpoints (calendar/list-calendars,
    of-the-day/json/upload+delete, plugins/<id>/static/<path>)
  - Starlark Apps (12 endpoints: status, install-pixlet, apps CRUD,
    repository browse/install, upload)
  - Font preview (/fonts/preview)
- Updated table of contents with the new sections.
- Added a footer note that the API blueprint mounts at /api/v3
  (app.py:144) and that SSE stream endpoints are defined directly on
  the Flask app at app.py:607-615.

ADVANCED_FEATURES.md
- Vegas Scroll Mode section was actually accurate (verified all
  config keys match src/vegas_mode/config.py:15-30).

- On-Demand Display section had multiple bugs:
  - 5 occurrences of port 5050 -> 5000
  - All API paths missing /v3 (e.g. /api/display/on-demand/start
    should be /api/v3/display/on-demand/start)
  - "Settings -> Plugin Management -> Show Now Button" UI flow doesn't
    exist. Real flow: open the plugin's tab in the second nav row,
    click Run On-Demand / Stop On-Demand.
  - "Python API Methods" section showed
    controller.show_on_demand() / clear_on_demand() /
    is_on_demand_active() / get_on_demand_info() — none of these
    methods exist on DisplayController. The on-demand machinery is
    all internal (_set_on_demand_*, _activate_on_demand, etc) and
    is driven through the cache_manager. Replaced the section with
    a note pointing to the REST API.
  - All Use Case Examples used the same fictional Python calls.
    Replaced with curl examples against the real API.

- Cache Management section claimed "On-demand display uses Redis cache
  keys". LEDMatrix doesn't use Redis — verified with grep that
  src/cache_manager.py has no redis import. The cache is file-based,
  managed by CacheManager (file at /var/cache/ledmatrix/ or fallback
  paths). Rewrote the manual recovery section:
  - Removed redis-cli commands
  - Replaced cache.delete() Python calls with cache.clear_cache()
    (the real public method per the same bug already flagged in
    PLUGIN_API_REFERENCE.md)
  - Replaced "Settings -> Cache Management" with the real Cache tab
  - Documented the actual cache directory candidates

- Background Data Service section:
  - Used "nfl_scoreboard" as the plugin id in the example.
    The real plugin is "football-scoreboard" (handles both NFL and
    NCAA). Fixed.
  - "Implementation Status: Phase 1 NFL only / Phase 2 planned"
    section was severely outdated. The background service is now
    used by all sports scoreboards (football, hockey, baseball,
    basketball, soccer, lacrosse, F1, UFC), the odds ticker, and
    the leaderboard plugin. Replaced with a current "Plugins using
    the background service" note.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix plugin config + store + dependency docs

PLUGIN_STORE_GUIDE.md
- 19 occurrences of port 5050 -> 5000
- All API paths missing /v3 (e.g. /api/plugins/install ->
  /api/v3/plugins/install). Bulk fix.

PLUGIN_REGISTRY_SETUP_GUIDE.md
- Same port + /api/v3 fixes (3 occurrences each)
- "Go to Plugin Store tab" -> "Open the Plugin Manager tab and scroll
  to the Install from GitHub section" (the real flow for registry
  setup is the GitHub install section, not the Plugin Store search)

PLUGIN_CONFIG_QUICK_START.md
- Port 5001 -> 5000 (5001 is the dev_server.py default, not the web UI)
- "Plugin Store tab" install flow -> real Plugin Manager + Plugin Store
  section + per-plugin tab in second nav row
- Removed reference to PLUGIN_CONFIG_TABS_SUMMARY.md (archived doc)

PLUGIN_CONFIGURATION_TABS.md
- "Plugin Management vs Configuration" section confusingly described
  a "Plugins Tab" that doesn't exist as a single thing. Rewrote to
  describe the real two-piece structure: Plugin Manager tab (browse,
  install, toggle) vs per-plugin tabs (configure individual plugins).

PLUGIN_DEPENDENCY_GUIDE.md
- Port 5001 -> 5000

PLUGIN_DEPENDENCY_TROUBLESHOOTING.md
- Wrong port (8080) and wrong UI nav ("Plugin Store or Plugin
  Management"). Fixed to the real flow.

PLUGIN_QUICK_REFERENCE.md
- "Plugin Location: ./plugins/ directory" -> default is plugin-repos/
  (verified in config/config.template.json:130 and
  display_controller.py:132). plugins/ is a fallback.
- File structure diagram showed plugins/ -> plugin-repos/.
- Web UI install flow: "Plugin Store tab" -> "Plugin Manager tab ->
  Plugin Store section". Also fixed Configure ⚙️ button (doesn't
  exist) and "Drag and drop reorder" (not implemented).
- API examples: replaced ad-hoc Python pseudocode with real curl
  examples against /api/v3/plugins/* endpoints. Pointed at
  REST_API_REFERENCE.md for the full list.
- "Migration Path Phase 1-5" was a roadmap written before the plugin
  system shipped. The plugin system is now stable and live. Removed
  the migration phases as they're history, not a roadmap.
- "Quick Migration" section called scripts/migrate_to_plugins.py
  which doesn't exist anywhere in the repo. Removed.
- "Plugin Registry Structure" referenced
  ChuckBuilds/ledmatrix-plugin-registry which doesn't exist. The
  real registry is ChuckBuilds/ledmatrix-plugins. Fixed.
- "Next Steps" / "Questions to Resolve" sections were
  pre-implementation planning notes. Replaced with a "Known
  Limitations" section that documents the actually-real gaps
  (sandboxing, resource limits, ratings, auto-updates).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix misc remaining docs (architecture, dev quickref, sub-dir READMEs)

PLUGIN_ARCHITECTURE_SPEC.md
- Added a banner at the top noting this is a historical design doc
  written before the plugin system shipped. The doc is ~1900 lines
  with 13 stale /api/plugins/* paths (real is /api/v3/plugins/*),
  references to web_interface_v2.py (current is app.py), and a
  Migration Strategy / Implementation Roadmap that's now history.
  Banner points readers at the current docs
  (PLUGIN_DEVELOPMENT_GUIDE, PLUGIN_API_REFERENCE,
  REST_API_REFERENCE) without needing to retrofit every section.

PLUGIN_CONFIG_ARCHITECTURE.md
- 10 occurrences of /api/plugins/* missing /v3 prefix. Bulk fixed.

DEVELOPER_QUICK_REFERENCE.md
- cache_manager.delete("key") -> cache_manager.clear_cache("key")
  with comment noting delete() doesn't exist. Same bug already
  documented in PLUGIN_API_REFERENCE.md.

SSH_UNAVAILABLE_AFTER_INSTALL.md
- 4 occurrences of port 5001 -> 5000 in AP-mode and Ethernet/WiFi
  recovery instructions.

PLUGIN_CUSTOM_ICONS_FEATURE.md
- Port 5001 -> 5000.

CONFIG_DEBUGGING.md
- Documented /api/v3/config/plugin/<id> and /api/v3/config/validate
  endpoints don't exist. Replaced with the real endpoints:
  /api/v3/config/main, /api/v3/plugins/schema?plugin_id=,
  /api/v3/plugins/config?plugin_id=. Added a note that validation
  runs server-side automatically on POST.

STARLARK_APPS_GUIDE.md
- "Plugins -> Starlark Apps" UI navigation path doesn't exist (5
  occurrences). Replaced with the real path: Plugin Manager tab,
  then the per-plugin Starlark Apps tab in the second nav row.
- "Navigate to Plugins" install step -> Plugin Manager tab.

web_interface/README.md
- Documented several endpoints that don't exist in the api_v3
  blueprint:
  - GET /api/v3/plugins (list) -> /api/v3/plugins/installed
  - GET /api/v3/plugins/<id> -> doesn't exist
  - POST /api/v3/plugins/<id>/config -> POST /api/v3/plugins/config
  - GET /api/v3/plugins/<id>/enable + /disable -> POST /api/v3/plugins/toggle
  - GET /api/v3/store/plugins -> /api/v3/plugins/store/list
  - POST /api/v3/store/install/<id> -> POST /api/v3/plugins/install
  - POST /api/v3/store/uninstall/<id> -> POST /api/v3/plugins/uninstall
  - POST /api/v3/store/update/<id> -> POST /api/v3/plugins/update
  - POST /api/v3/display/start/stop/restart -> POST /api/v3/system/action
  - GET /api/v3/display/status -> GET /api/v3/system/status
- Also fixed config/secrets.json -> config/config_secrets.json
- Replaced the per-section endpoint duplication with a current real
  endpoint list and a pointer to docs/REST_API_REFERENCE.md.
- Documented that SSE stream endpoints are defined directly on the
  Flask app at app.py:607-615, not in the api_v3 blueprint.

scripts/install/README.md
- Was missing 3 of the 9 install scripts in the directory:
  one-shot-install.sh, configure_wifi_permissions.sh, and
  debug_install.sh. Added them with brief descriptions.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: clarify plugin paths and fix systemd manual install bug

PLUGIN_DEVELOPMENT_GUIDE.md
- Added a "Plugin directory note" callout near the top explaining
  the plugins/ vs plugin-repos/ split:
  - Dev workflow uses plugins/ (where dev_plugin_setup.sh creates
    symlinks)
  - Production / Plugin Store uses plugin-repos/ (the configurable
    default per config.template.json:130)
  - The plugin loader falls back to plugins/ so dev symlinks are
    picked up automatically (schema_manager.py:77)
  - User can set plugins_directory to "plugins" in the General tab
    if they want both to share a directory

CLAUDE.md
- The Project Structure section had plugins/ and plugin-repos/
  exactly reversed:
  - Old: "plugins/ - Installed plugins directory (gitignored)"
         "plugin-repos/ - Development symlinks to monorepo plugin dirs"
  - Real: plugin-repos/ is the canonical Plugin Store install
    location and is not gitignored. plugins/* IS gitignored
    (verified in .gitignore) and is the legacy/dev location used by
    scripts/dev/dev_plugin_setup.sh.
  Reversed the descriptions and added line refs.

systemd/README.md
- "Manual Installation" section told users to copy the unit file
  directly to /etc/systemd/system/. Verified the unit file in
  systemd/ledmatrix.service contains __PROJECT_ROOT_DIR__
  placeholders that the install scripts substitute at install time.
  A user following the manual steps would get a service that fails
  to start with "WorkingDirectory=__PROJECT_ROOT_DIR__" errors.
  Added a clear warning and a sed snippet that substitutes the
  placeholder before installing.

src/common/README.md
- Was missing 2 of the 11 utility modules in the directory
  (verified with ls): permission_utils.py and cli.py. Added brief
  descriptions for both.

Out-of-scope code bug found while auditing (flagged but not fixed):
- scripts/dev/dev_plugin_setup.sh:9 sets PROJECT_ROOT="$SCRIPT_DIR"
  which resolves to scripts/dev/, not the project root. This means
  the script's PLUGINS_DIR resolves to scripts/dev/plugins/ instead
  of the project's plugins/ — confirmed by the existence of
  scripts/dev/plugins/of-the-day/ from prior runs. Real fix is to
  set PROJECT_ROOT="$(cd "$SCRIPT_DIR/../.." && pwd)". Not fixing in
  this docs PR.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: flag aspirational/regressed features in plugin docs

These docs describe features that exist as documented in the doc but
either never wired up or regressed when v3 shipped. Each gets a clear
status banner so plugin authors don't waste time chasing features that
don't actually work.

FONT_MANAGER.md
- The "For Plugin Developers / Plugin Font Registration" section
  documents adding a "fonts" block to manifest.json that gets
  registered via FontManager.register_plugin_fonts(). The method
  exists at src/font_manager.py:150 but is **never called from
  anywhere** in the codebase (verified: zero callers). A plugin
  shipping a manifest "fonts" block has its fonts silently ignored.
  Added a status warning and a note about how to actually ship plugin
  fonts (regular files in the plugin dir, loaded directly).

PLUGIN_IMPLEMENTATION_SUMMARY.md
- Added a top-level status banner.
- Architecture diagram referenced src/plugin_system/registry_manager.py
  (which doesn't exist) and listed plugins/ as the install location.
  Replaced with the real file list (plugin_loader, schema_manager,
  health_monitor, operation_queue, state_manager) and pointed at
  plugin-repos/ as the default install location.
- "Dependency Management: Virtual Environments" — verified there's no
  per-plugin venv. Removed the bullet and added a note that plugin
  Python deps install into the system Python environment, with no
  conflict resolution.
- "Permission System: File Access Control / Network Access /
  Resource Limits / CPU and memory constraints" — none of these
  exist. There's a resource_monitor.py and health_monitor.py for
  metrics/warnings, but no hard caps or sandboxing. Replaced the
  section with what's actually implemented and a clear note that
  plugins run in the same process with full file/network access.

PLUGIN_CUSTOM_ICONS.md and PLUGIN_CUSTOM_ICONS_FEATURE.md
- The custom-icon feature was implemented in the v2 web interface
  via a getPluginIcon() helper in templates/index_v2.html that read
  the manifest "icon" field. When the v3 web interface was built,
  that helper wasn't ported. Verified in
  web_interface/templates/v3/base.html:515 and :774, plugin tab
  icons are hardcoded to `fas fa-puzzle-piece`. The "icon" field in
  plugin manifests is currently silently ignored (verified with grep
  across web_interface/ and src/plugin_system/ — zero non-action-
  related reads of plugin.icon or manifest.icon).
- Added a status banner to both docs noting the regression so plugin
  authors don't think their custom icons are broken in their own
  plugin code.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix .cursor/ helper docs

The .cursor/ directory holds the dev-side helper docs that Cursor and
contributors using AI tooling rely on to bootstrap plugin development.
Several of them had the same bug patterns as the user-facing docs.

.cursor/plugin_templates/QUICK_START.md
- "Adding Image Rendering" section showed
  display_manager.draw_image(image, x=0, y=0). That method doesn't
  exist on DisplayManager (same bug as PLUGIN_API_REFERENCE.md and
  PLUGIN_DEVELOPMENT_GUIDE.md). Replaced with the canonical
  display_manager.image.paste((x,y)) pattern, including the
  transparency-mask form.

.cursor/plugins_guide.md
- 10 occurrences of ./dev_plugin_setup.sh — the script lives at
  scripts/dev/dev_plugin_setup.sh, so anyone copy-pasting these
  examples gets "command not found". Bulk fixed via sed.
- "Test with emulator: python run.py --emulator" — there's no
  --emulator flag. Replaced with the real options:
  EMULATOR=true python3 run.py for the full display, or
  scripts/dev_server.py for the dev preview.
- Secrets management section showed a fictional
  "config_secrets": { "api_key": "my-plugin.api_key" } reference
  field. Verified in src/config_manager.py:162-172 that secrets are
  loaded by deep-merging config_secrets.json into the main config.
  There is no separate reference field — just put the secret under
  the same plugin namespace and read it from the merged config.
  Rewrote the section with the real pattern.
- "ssh pi@raspberrypi" -> "ssh ledpi@your-pi-ip" (consistent with
  the rest of LEDMatrix docs which use ledpi as the default user)

.cursor/README.md
- Same ./dev_plugin_setup.sh -> ./scripts/dev/dev_plugin_setup.sh
  fix (×6 occurrences via replace_all).
- Same "python run.py --emulator" -> "EMULATOR=true python3 run.py"
  fix. Also added a pointer to scripts/dev_server.py for previewing
  plugins without running the full display.
- "Example Plugins: plugins/hockey-scoreboard/" — the canonical
  source is the ledmatrix-plugins repo. Installed copies land in
  plugin-repos/ or plugins/. Updated the line to point at the
  ledmatrix-plugins repo and explain both local locations.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix .cursorrules — the file Cursor auto-loads to learn the API

This is the file that Cursor reads to learn how plugin development
works. Stale entries here directly mislead AI-assisted plugin authors
on every new plugin. Several of the same bug patterns I've been
fixing in the user-facing docs were here too.

Display Manager section (highest impact)
- "draw_image(image, x, y): Draw PIL Image" — that method doesn't
  exist on DisplayManager. Same bug already fixed in
  PLUGIN_API_REFERENCE.md, PLUGIN_DEVELOPMENT_GUIDE.md,
  ledmatrix-stocks/README.md, and .cursor/plugin_templates/QUICK_START.md.
  Removed the bullet and replaced it with a paragraph explaining the
  real pattern: paste onto display_manager.image directly, then
  update_display(). Includes the transparency-mask form.
- Added the small_font/centered args to draw_text() since they're
  the ones that matter most for new plugin authors
- Added draw_weather_icon since it's commonly used

Cache Manager section
- "delete(key): Remove cached value" — there's no delete() method
  on CacheManager. The real method is clear_cache(key=None) (also
  removes everything when called without args). Same bug as before.
- Added get_cached_data_with_strategy and get_background_cached_data
  since contributors will hit these when working on sports plugins

Plugin System Overview
- "loaded from the plugins/ directory" — clarified that the default
  is plugin-repos/ (per config.template.json:130) with plugins/ as
  the dev fallback used by scripts/dev/dev_plugin_setup.sh

Plugin Development Workflow
- ./dev_plugin_setup.sh -> ./scripts/dev/dev_plugin_setup.sh (×2)
- Manual setup step "Create directory in plugins/<plugin-id>/" ->
  plugin-repos/<plugin-id>/ as the canonical location
- "Use emulator: python run.py --emulator or ./run_emulator.sh"
  — the --emulator flag doesn't exist; ./run_emulator.sh isn't at
  root (it lives at scripts/dev/run_emulator.sh). Replaced with the
  real options: scripts/dev_server.py for dev preview, or
  EMULATOR=true python3 run.py for the full emulator path.

Configuration Management
- "Reference secrets via config_secrets key in main config" — this
  is the same fictional reference syntax I just fixed in
  .cursor/plugins_guide.md. Verified in src/config_manager.py:162-172
  that secrets are deep-merged into the main config; there's no
  separate reference field. Replaced with a clear explanation of
  the deep-merge approach.

Code Organization
- "plugins/<plugin-id>/" -> the canonical location is
  plugin-repos/<plugin-id>/ (or its dev-time symlink in plugins/)
- "see plugins/hockey-scoreboard/ as reference" — the canonical
  source for example plugins is the ledmatrix-plugins repo. Updated
  the pointer.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Add LICENSE (GPL-3.0) and CONTRIBUTING.md

LICENSE
- The repository previously had no LICENSE file. The README and every
  downstream plugin README already reference GPL-3.0 ("same as
  LEDMatrix project"), but the canonical license text was missing —
  contributors had no formal record of what they were contributing
  under, and GitHub couldn't auto-detect the license for the repo
  banner.
- Added the canonical GPL-3.0 text from
  https://www.gnu.org/licenses/gpl-3.0.txt (verbatim, 674 lines).
- Compatibility verified: rpi-rgb-led-matrix is GPL-2.0-or-later
  (per its COPYING file and README; the "or any later version" clause
  in lib/*.h headers makes GPL-3.0 distribution legal).

CONTRIBUTING.md
- The repository had no CONTRIBUTING file. New contributors had to
  reconstruct the dev setup from DEVELOPMENT.md, PLUGIN_DEVELOPMENT_GUIDE.md,
  SUBMISSION.md, and the root README.
- Added a single page covering: dev environment setup (preview
  server, emulator, hardware), running tests, PR submission flow,
  commit message convention, plugin contribution pointer, and the
  license terms contributors are agreeing to.

> Note for the maintainer: I (the AI assistant doing this audit) am
> selecting GPL-3.0 because every reference in the existing
> documentation already says GPL-3.0 — this commit just makes that
> declaration legally binding by adding the actual file. Please
> confirm during PR review that GPL-3.0 is what you want; if you
> prefer a different license, revert this commit before merging.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Add CODE_OF_CONDUCT, SECURITY, PR template; link them from README

Tier 1 organizational files that any open-source project at
LEDMatrix's maturity is expected to have. None of these existed
before. They're additive — no existing content was rewritten.

CODE_OF_CONDUCT.md
- Contributor Covenant 2.1 (the de facto standard for open-source
  projects). Mentions both the Discord and the GitHub Security
  Advisories channel for reporting violations.

SECURITY.md
- Private vulnerability disclosure flow with two channels: GitHub
  Security Advisories (preferred) and Discord DM.
- Documents the project's known security model as intentional
  rather than vulnerabilities: no web UI auth, plugins run
  unsandboxed, display service runs as root for GPIO access,
  config_secrets.json is plaintext. These match the limitations
  already called out in PLUGIN_QUICK_REFERENCE.md and the audit
  flagging from earlier in this PR.
- Out-of-scope section points users at upstream
  (rpi-rgb-led-matrix, third-party plugins) so reports land in the
  right place.

.github/PULL_REQUEST_TEMPLATE.md
- 10-line checklist that prompts for the things that would have
  caught the bugs in this very PR: did you load the changed plugin
  once, did you update docs alongside code, are there any plugin
  compatibility implications.
- Linked from CONTRIBUTING.md for the full flow.

README.md
- Added a License section near the bottom (the README previously
  said nothing about the license despite the project being GPL-3.0).
- Added a Contributing section pointing at CONTRIBUTING.md and
  SECURITY.md.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* Customize bug report template for LEDMatrix hardware

The bug_report.md template was the GitHub default and asked
"Desktop (OS/Browser/Version)" and "Smartphone (Device/OS)" — neither
of which is relevant for a project that runs on a Raspberry Pi with
hardware LED panels. A user filing a bug under the old template was
giving us none of the information we'd actually need to triage it.

Replaced with a LEDMatrix-aware template that prompts for:
- Pi model, OS/kernel, panel type, HAT/Bonnet, PWM jumper status,
  display chain dimensions
- LEDMatrix git commit / release tag
- Plugin id and version (if the bug is plugin-related)
- Relevant config snippet (with redaction reminder for API keys)
- journalctl log excerpt with the exact command to capture it
- Optional photo of the actual display for visual issues

Kept feature_request.md as-is — generic content there is fine.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix bare /api/plugins paths in PLUGIN_CONFIGURATION_TABS

Found 5 more bare /api/plugins/* paths in PLUGIN_CONFIGURATION_TABS.md
that I missed in the round 2 sweep — they're inside data flow diagrams
and prose ("loaded via /api/plugins/installed", etc.) so the earlier
grep over Markdown code blocks didn't catch them. Fixed all 5 to use
/api/v3/plugins/* (the api_v3 blueprint mount path verified at
web_interface/app.py:144).

Also added a status banner noting that the "Implementation Details"
section references the pre-v3 file layout (web_interface_v2.py,
templates/index_v2.html) which no longer exists. The current
implementation is in web_interface/app.py, blueprints/api_v3.py, and
templates/v3/. Same kind of historical drift I flagged in
PLUGIN_ARCHITECTURE_SPEC.md and the PLUGIN_CUSTOM_ICONS_FEATURE doc.
The user-facing parts of the doc (Overview, Features, Form Generation
Process) are still accurate.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs(widgets): list the 20 undocumented built-in widgets

The widget registry README documented 3 widgets (file-upload,
checkbox-group, custom-feeds) but the directory contains 23 registered
widgets total. A plugin author reading this doc would think those 3
were the only built-in options and either reach for a custom widget
unnecessarily or settle for a generic text input.

Verified the actual list with:
  grep -h "register('" web_interface/static/v3/js/widgets/*.js \
    | sed -E "s|.*register\\('([^']+)'.*|\\1|" | sort -u

Added an "Other Built-in Widgets" section after the 3 detailed
sections, listing the remaining 20 with one-line descriptions
organized by category:
- Inputs (6): text-input, textarea, number-input, email-input,
  url-input, password-input
- Selectors (7): select-dropdown, radio-group, toggle-switch,
  slider, color-picker, font-selector, timezone-selector
- Date/time/scheduling (4): date-picker, day-selector, time-range,
  schedule-picker
- Composite/data-source (2): array-table, google-calendar-picker
- Internal (2): notification, base-widget

Pointed at the .js source files as the canonical source for each
widget's exact schema and options — keeps this list low-maintenance
since I'm not duplicating each widget's full options table.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix README_NBA_LOGOS and PLUGIN_CONFIGURATION_GUIDE

scripts/README_NBA_LOGOS.md
- "python download_nba_logos.py" — wrong on two counts. The script
  is at scripts/download_nba_logos.py (not the project root), and
  "python" is Python 2 on most systems. Replaced all 4 occurrences
  with "python3 scripts/download_nba_logos.py".
- The doc framed itself as the way to set up "the NBA leaderboard".
  The basketball/leaderboard functionality is now in the
  basketball-scoreboard and ledmatrix-leaderboard plugins (in the
  ledmatrix-plugins repo), which auto-download logos on first run.
  Reframed the script as a pre-population utility for offline / dev
  use cases.
- Bumped the documented Python minimum from 3.7 to 3.9 to match
  the rest of the project.

docs/PLUGIN_CONFIGURATION_GUIDE.md
- The "Plugin Manifest" example was missing 3 fields the plugin
  loader actually requires: id, entry_point, and class_name. A
  contributor copying this manifest verbatim would get
  PluginError("No class_name in manifest") at load time — the same
  loader bug already found in stock-news. Added all three.
- The same example showed config_schema as an inline object. The
  loader expects config_schema to be a file path string (e.g.
  "config_schema.json") with the actual schema in a separate JSON
  file — verified earlier in this audit. Fixed.
- Added a paragraph explaining the loader's required fields and
  the case-sensitivity rule on class_name (the bug that broke
  hello-world's manifest before this PR fixed it).
- "Plugin Manager Class" example had the wrong constructor
  signature: (config, display_manager, cache_manager, font_manager).
  The real BasePlugin.__init__ at base_plugin.py:53-60 takes
  (plugin_id, config, display_manager, cache_manager, plugin_manager).
  A copy-pasted example would TypeError on instantiation. Fixed,
  including a comment noting which attributes BasePlugin sets up.
- Renamed the example class from MyPluginManager to MyPlugin to
  match the project convention (XxxPlugin / XxxScoreboardPlugin
  in actual plugins).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs(requirements): document optional dependencies (scipy, psutil, Flask-Limiter)

A doc-vs-code crosscheck of every Python import in src/ and
web_interface/ against requirements.txt found 3 packages that the
code uses but requirements.txt doesn't list. Verified with grep that
all 3 are wrapped in try/except blocks with documented fallback
paths, so they're optional features rather than missing required
deps:

- scipy           src/common/scroll_helper.py:26
                  → from scipy.ndimage import shift; HAS_SCIPY flag.
                  Used for sub-pixel interpolation in scrolling.
                  Falls back to a simpler shift algorithm without it.

- psutil          src/plugin_system/resource_monitor.py:15
                  → import psutil; PSUTIL_AVAILABLE flag. Used for
                  per-plugin CPU/memory monitoring. Silently no-ops
                  without it.

- flask-limiter   web_interface/app.py:42-43
                  → from flask_limiter import Limiter; wrapped at the
                  caller. Used for accidental-abuse rate limiting on
                  the web interface (not security). Web interface
                  starts without rate limiting when missing.

These were latent in two ways:
1. A user reading requirements.txt thinks they have the full feature
   set after `pip install -r requirements.txt`, but they don't get
   smoother scrolling, plugin resource monitoring, or rate limiting.
2. A contributor who deletes one of the packages from their dev env
   wouldn't know which feature they just lost — the fallbacks are
   silent.

Added an "Optional dependencies" section at the bottom of
requirements.txt with the version constraint, the file:line where
each is used, the feature it enables, and the install command. The
comment-only format means `pip install -r requirements.txt` still
gives the minimal-feature install (preserving current behavior),
while users who want the full feature set can copy the explicit
pip install commands.

Other findings from the same scan that came back as false positives
or known issues:
- web_interface_v2: dead pattern flagged in earlier iteration
  (still no real implementation; affects 11+ plugins via the same
  try/except dead-fallback pattern)
- urllib3: comes with `requests` transitively
- All 'src.', 'web_interface.', 'rgbmatrix', 'RGBMatrixEmulator'
  imports: internal modules
- base_plugin / plugin_manager / store_manager / mocks /
  visual_display_manager: relative imports to local modules
- freetype: false positive (freetype-py is in requirements.txt
  under the package name)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: fix broken file references found by path-existence crosscheck

Ran a doc-vs-filesystem crosscheck: extracted every backtick-quoted
path with a file extension or known directory prefix from docs/*.md
and verified each exists. After filtering false positives
(placeholder paths, config keys mistaken for paths, paths inside
docs that already have historical-status banners), found 4 real
broken references — 3 fixed in docs, 1 fixed by creating the missing
file:

docs/HOW_TO_RUN_TESTS.md:339
- Claimed ".github/workflows/tests.yml" exists and runs pytest on
  multiple Python versions in CI. There is no such workflow.
  The only GitHub Actions file is security-audit.yml (bandit + semgrep).
- Pytest runs locally but is NOT gated on PRs.
- Replaced the fictional CI section with the actual state and a
  note explaining how someone could contribute a real test workflow.

docs/MIGRATION_GUIDE.md:92
- Referenced scripts/fix_perms/README.md "(if exists)" — the
  hedge betrays that the writer wasn't sure. The README didn't
  exist. The 6 scripts in scripts/fix_perms/ were never documented.
- Created the missing scripts/fix_perms/README.md from scratch
  with one-line descriptions of all 6 scripts (fix_assets,
  fix_cache, fix_plugin, fix_web, fix_nhl_cache, safe_plugin_rm)
  + when-to-use-each guidance + usage examples.
- Updated MIGRATION_GUIDE link to drop the "(if exists)" hedge
  since the file now exists.

docs/FONT_MANAGER.md:376
- "See test/font_manager_example.py for a complete working example"
  — that file does not exist. Verified by listing test/ directory.
- Replaced with a pointer to src/font_manager.py itself and the
  existing scoreboard base classes in src/base_classes/ that
  actually use the font manager API in production.

Path-existence check methodology:
- Walked docs/ recursively, regex-extracted backtick-quoted paths
  matching either /\.(py|sh|json|yml|yaml|md|txt|service|html|js|css|ttf|bdf|png)/
  or paths starting with known directory prefixes (scripts/, src/,
  config/, web_interface/, systemd/, assets/, docs/, test/, etc.)
- Filtered out URLs, absolute paths (placeholders), and paths
  without slashes (likely not relative refs).
- Checked existence relative to project root.
- Out of 80 unique relative paths in docs/, 32 didn't exist on
  disk. Most were false positives (configkeys mistaken for paths,
  example placeholders like 'assets/myfont.ttf', historical
  references inside docs that already have status banners). The 4
  above were genuine broken refs.

This pattern is reusable for future iterations and worth wiring
into CI (link checker like lychee, scoped to fenced code paths
rather than just markdown links, would catch the same class).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* docs: address CodeRabbit review comments on #306

Reviewed all 12 CodeRabbit comments on PR #306, verified each against
the current code, and fixed the 11 valid ones. The 12th finding is a
real code bug (cache_manager.delete() calls in api_helper.py and
resource_monitor.py) that's already in the planned follow-up code-fix
PR, so it stays out of this docs PR.

Fixed:

.cursor/plugins_guide.md, .cursor/README.md, .cursorrules
- I claimed "there is no --emulator flag" in 3 places. Verified in
  run.py:19-20 that the -e/--emulator flag is defined and functional
  (it sets os.environ["EMULATOR"]="true" before the display imports).
  Other docs I didn't touch (.cursor/plugin_templates/QUICK_START.md,
  docs/PLUGIN_DEVELOPMENT_GUIDE.md) already use the flag correctly.
  Replaced all 3 wrong statements with accurate guidance that
  both forms work and explains the CLI flag's relationship to the
  env var.

.cursorrules, docs/GETTING_STARTED.md, docs/WEB_INTERFACE_GUIDE.md,
docs/PLUGIN_DEVELOPMENT_GUIDE.md
- Four places claimed "the plugin loader also falls back to plugins/".
  Verified that PluginManager.discover_plugins()
  (src/plugin_system/plugin_manager.py:154) only scans the
  configured directory — no fallback. The fallback to plugins/
  exists only in two narrower places: store_manager.py:1700-1718
  (store install/update/uninstall operations) and
  schema_manager.py:70-80 (schema lookup for the web UI form
  generator). Rewrote all four mentions with the precise scope.
  Added a recommendation to set plugin_system.plugins_directory
  to "plugins" for the smoothest dev workflow with
  dev_plugin_setup.sh symlinks.

docs/FONT_MANAGER.md
- The "Status" warning told plugin authors to use
  display_manager.font_manager.resolve_font(...) as a workaround for
  loading plugin fonts. Verified in src/font_manager.py that
  resolve_font() takes a family name, not a file path — so the
  workaround as written doesn't actually work. Rewrote to tell
  authors to load the font directly with PIL or freetype-py in their
  plugin.
- The same section said "the user-facing font override system in the
  Fonts tab still works for any element that's been registered via
  register_manager_font()". Verified in
  web_interface/blueprints/api_v3.py:5404-5428 that
  /api/v3/fonts/overrides is a placeholder implementation that
  returns empty arrays and contains "would integrate with the actual
  font system" comments — the Fonts tab does not have functional
  integration with register_manager_font() or the override system.
  Removed the false claim and added an explicit note that the tab
  is a placeholder.

docs/ADVANCED_FEATURES.md:523
- The on-demand section said REST/UI calls write a request "into the
  cache manager (display_on_demand_config key)". Wrong — verified
  via grep that api_v3.py:1622 and :1687 write to
  display_on_demand_request, and display_on_demand_config is only
  written by the controller during activation
  (display_controller.py:1195, cleared at :1221). Corrected the key
  name and added controller file:line references so future readers
  can verify.

docs/ADVANCED_FEATURES.md:803
- "Plugins using the background service" paragraph listed all
  scoreboard plugins but an orphaned "⏳ MLB (baseball)" bullet
  remained below from the old version of the section. Removed the
  orphan and added "baseball/MLB" to the inline list for clarity.

web_interface/README.md
- The POST /api/v3/system/action action list was incomplete. Verified
  in web_interface/app.py:1383,1386 that enable_autostart and
  disable_autostart are valid actions. Added both.
- The Plugin Store section was missing
  GET /api/v3/plugins/store/github-status (verified at
  api_v3.py:3296). Added it.
- The SSE line-range reference was app.py:607-615 but line 619
  contains the "Exempt SSE streams from CSRF and add rate limiting"
  block that's semantically part of the same feature. Extended the
  range to 607-619.

docs/GETTING_STARTED.md
- Rows/Columns step said "Columns: 64 or 96 (match your hardware)".
  The web UI's validation accepts any integer in 16-128. Clarified
  that 64 and 96 are the common bundled-hardware values but the
  valid range is wider.

Not addressed (out of scope for docs PR):

- .cursorrules:184 CodeRabbit comment flagged the non-existent
  cache_manager.delete() calls in src/common/api_helper.py:287 and
  src/plugin_system/resource_monitor.py:343. These are real CODE
  bugs, not doc bugs, and they're the first item in the planned
  post-docs-refresh code-cleanup PR (see
  /home/chuck/.claude/plans/warm-imagining-river.md). The docs in
  this PR correctly state that delete() doesn't exist on
  CacheManager — the fix belongs in the follow-up code PR that
  either adds a delete() shim or updates the two callers.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Chuck <chuck@example.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.cursor/README.md

@@ -43,39 +43,48 @@ cp ../../.cursor/plugin_templates/*.template .
 2. **Using dev_plugin_setup.sh**:
 ```bash
 # Link from GitHub
-./dev_plugin_setup.sh link-github my-plugin
+./scripts/dev/dev_plugin_setup.sh link-github my-plugin
 
 # Link local repo
-./dev_plugin_setup.sh link my-plugin /path/to/repo
+./scripts/dev/dev_plugin_setup.sh link my-plugin /path/to/repo
 ```
 
-### Running Plugins
+### Running the Display
 
 ```bash
-# Emulator (development)
-python run.py --emulator
+# Emulator mode (development, no hardware required)
+python3 run.py --emulator
+# (equivalent: EMULATOR=true python3 run.py)
 
-# Hardware (production)
-python run.py
+# Hardware (production, requires the rpi-rgb-led-matrix submodule built)
+python3 run.py
 
-# As service
+# As a systemd service
 sudo systemctl start ledmatrix
+
+# Dev preview server (renders plugins to a browser without running run.py)
+python3 scripts/dev_server.py  # then open http://localhost:5001
 ```
 
+The `-e`/`--emulator` CLI flag is defined in `run.py:19-20` and
+sets `os.environ["EMULATOR"] = "true"` before any display imports,
+which `src/display_manager.py:2` then reads to switch between the
+hardware and emulator backends.
+
 ### Managing Plugins
 
 ```bash
 # List plugins
-./dev_plugin_setup.sh list
+./scripts/dev/dev_plugin_setup.sh list
 
 # Check status
-./dev_plugin_setup.sh status
+./scripts/dev/dev_plugin_setup.sh status
 
 # Update plugin(s)
-./dev_plugin_setup.sh update [plugin-name]
+./scripts/dev/dev_plugin_setup.sh update [plugin-name]
 
 # Unlink plugin
-./dev_plugin_setup.sh unlink <plugin-name>
+./scripts/dev/dev_plugin_setup.sh unlink <plugin-name>
 ```
 
 ## Using These Files with Cursor
@@ -118,9 +127,13 @@ Refer to `plugins_guide.md` for:
 - **Plugin System**: `src/plugin_system/`
 - **Base Plugin**: `src/plugin_system/base_plugin.py`
 - **Plugin Manager**: `src/plugin_system/plugin_manager.py`
-- **Example Plugins**: `plugins/hockey-scoreboard/`, `plugins/football-scoreboard/`
+- **Example Plugins**: see the
+  [`ledmatrix-plugins`](https://github.com/ChuckBuilds/ledmatrix-plugins)
+  repo for canonical sources (e.g. `plugins/hockey-scoreboard/`,
+  `plugins/football-scoreboard/`). Installed plugins land in
+  `plugin-repos/` (default) or `plugins/` (dev fallback).
 - **Architecture Docs**: `docs/PLUGIN_ARCHITECTURE_SPEC.md`
-- **Development Setup**: `dev_plugin_setup.sh`
+- **Development Setup**: `scripts/dev/dev_plugin_setup.sh`
 
 ## Getting Help