docs: correct stale file:line references and the loader-fallback contradiction

CLAUDE.md and .cursorrules disagreed about plugin-directory fallback
behavior; the code (SchemaManager.get_schema_path) probes plugins/
BEFORE plugin-repos/, and the main discovery path has no fallback at
all — both files now describe the real behavior, preferring symbol names
over line numbers so the references rot slower. REST_API_REFERENCE.md
pointed at app.py:144/:607 for mounts that live at :199/:799 and counted
92 routes where there are 94. PLUGIN_ARCHITECTURE_SPEC.md's historical
banner gains a note that its example imports
(src/plugin_system/base_classes/*_plugin.py) never shipped — the real
base classes are src.base_classes.sports.SportsCore and
src.base_classes.hockey.Hockey.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SXb4mKcAkVaxkeTb3YnAdr

CLAUDE.md

@@ -6,12 +6,16 @@
 - `config/config.json` — User plugin configuration (persists across plugin reinstalls)
 - `plugin-repos/` — **Default** plugin install directory used by the
   Plugin Store, set by `plugin_system.plugins_directory` in
-  `config.json` (default per `config/config.template.json:130`).
+  `config.json` (default per `config/config.template.json:167`).
   Not gitignored.
 - `plugins/` — Legacy/dev plugin location. Gitignored (`plugins/*`).
   Used by `scripts/dev/dev_plugin_setup.sh` for symlinks. The plugin
-  loader falls back to it when something isn't found in `plugin-repos/`
-  (`src/plugin_system/schema_manager.py:77`).
+  loader does NOT fall back to it — `PluginManager.discover_plugins()`
+  (`src/plugin_system/plugin_manager.py`) scans only the configured
+  directory. Fallbacks exist in two narrower places: store operations
+  (`StoreManager._find_plugin_path()` in `store_manager.py`) and schema
+  lookup (`SchemaManager.get_schema_path()` in `schema_manager.py`,
+  which probes `plugins/` *before* `plugin-repos/`).
 
 ## Plugin System
 - Plugins inherit from `BasePlugin` in `src/plugin_system/base_plugin.py`
@@ -33,7 +37,7 @@
 
 ## Skin System (visual overlays for sports scoreboards)
 - Skins live in `skins/<skin-id>/` (skin.json + skin.py), NOT in plugin dirs — plugin reinstall deletes plugin dirs
-- Core: `src/skin_system/` (ScoreboardSkin, SkinContext, runtime); hook: `SportsCore._render_game()` in `src/base_classes/sports.py`
+- Core: `src/skin_system/` (ScoreboardSkin, SkinContext, runtime); hook: `SportsCore._render_game()` in `src/base_classes/sports/core.py`
 - Skins render onto `ctx.canvas` only; fallback to built-in renderer on `False`/exception (3 strikes disables for session)
 - View-model guaranteed keys are frozen (see `test/test_skin_system.py::TestViewModelContract`) — renaming keys in `_extract_game_details_common` or sport extractors breaks published skins
 - Validate skins headlessly: `python scripts/validate_skin.py --skin <id>`; docs: `docs/SKIN_SYSTEM.md`, `docs/CREATING_SKINS.md`