feat: add dev preview server and CLI render script (#264)

* fix(web): wire up "Check & Update All" plugins button

window.updateAllPlugins was never assigned, so the button always showed
"Bulk update handler unavailable." Wire it to PluginInstallManager.updateAll(),
add per-plugin progress feedback in the button text, show a summary
notification on completion, and skip redundant plugin list reloads.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* feat: add dev preview server, CLI render script, and visual test display manager

Adds local development tools for rapid plugin iteration without deploying to RPi:

- VisualTestDisplayManager: renders real pixels via PIL (same fonts/interface as production)
- Dev preview server (Flask): interactive web UI with plugin picker, auto-generated config
  forms, zoom/grid controls, and mock data support for API-dependent plugins
- CLI render script: render any plugin to PNG for AI-assisted visual feedback loops
- Updated test runner and conftest to auto-detect plugin-repos/ directory

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix(dev-preview): address code review issues

- Use get_logger() from src.logging_config instead of logging.getLogger()
  in visual_display_manager.py to match project logging conventions
- Eliminate duplicate public/private weather draw methods — public draw_sun/
  draw_cloud/draw_rain/draw_snow now delegate to the private _draw_* variants
  so plugins get consistent pixel output in tests vs production
- Default install_deps=False in dev_server.py and render_plugin.py — dev
  scripts don't need to run pip install; developers are expected to have
  plugin deps installed in their venv already
- Guard plugins_dir fixture against PermissionError during directory iteration
- Fix PluginInstallManager.updateAll() to fall back to window.installedPlugins
  when PluginStateManager.installedPlugins is empty (plugins_manager.js
  populates window.installedPlugins independently of PluginStateManager)
- Remove 5 debug console.log statements from plugins_manager.js button setup
  and initialization code

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix(scroll): fix scroll completion to prevent multi-pass wrapping

Change required_total_distance from total_scroll_width + display_width to
total_scroll_width alone. The scrolling image already contains display_width
pixels of blank initial padding, so reaching total_scroll_width means all
content has scrolled off-screen. The extra display_width term was causing
1-2+ unnecessary wrap-arounds, making the same games appear multiple times
and producing a black flicker between passes.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* fix(dev-preview): address PR #264 code review findings

- docs/DEV_PREVIEW.md: add bash language tag to fenced code block
- scripts/dev_server.py: add MAX/MIN_WIDTH/HEIGHT constants and validate
  width/height in render endpoint; add structured logger calls to
  discover_plugins (missing dirs, hidden entries, missing manifest,
  JSON/OS errors, duplicate ids); add type annotations to all helpers
- scripts/render_plugin.py: add MIN/MAX_DIMENSION validation after
  parse_args; replace prints with get_logger() calls; narrow broad
  Exception catches to ImportError/OSError/ValueError in plugin load
  block; add type annotations to all helpers and main(); rename unused
  module binding to _module
- scripts/run_plugin_tests.py: wrap plugins_path.iterdir() in
  try/except PermissionError with fallback to plugin-repos/
- scripts/templates/dev_preview.html: replace non-focusable div toggles
  with button role="switch" + aria-checked; add keyboard handlers
  (Enter/Space); sync aria-checked in toggleGrid/toggleAutoRefresh
- src/common/scroll_helper.py: early-guard zero total_scroll_width to
  keep scroll_position at 0 and skip completion/wrap logic
- src/plugin_system/testing/visual_display_manager.py: forward color
  arg in draw_cloud -> _draw_cloud; add color param to _draw_cloud;
  restore _scrolling_state in reset(); narrow broad Exception catches in
  _load_fonts to FileNotFoundError/OSError/ImportError; add explicit
  type annotations to draw_text
- test/plugins/test_visual_rendering.py: use context manager for
  Image.open in test_save_snapshot
- test/plugins/conftest.py: add return type hints to all fixtures

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

* chore: add bandit and gitleaks pre-commit hooks

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Chuck <chuck@example.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

test/plugins/conftest.py

@@ -8,7 +8,7 @@ import sys
 import json
 from pathlib import Path
 from unittest.mock import MagicMock, Mock
-from typing import Dict, Any
+from typing import Any, Dict, Generator, Optional
 
 # Add project root to path
 project_root = Path(__file__).parent.parent.parent
@@ -20,13 +20,33 @@ os.environ['EMULATOR'] = 'true'
 
 
 @pytest.fixture
-def plugins_dir():
-    """Get the plugins directory path."""
-    return project_root / 'plugins'
+def plugins_dir() -> Path:
+    """Get the plugins directory path.
+
+    Checks plugins/ first, then falls back to plugin-repos/
+    for monorepo development environments.
+    """
+    plugins_path = project_root / 'plugins'
+    plugin_repos_path = project_root / 'plugin-repos'
+
+    # Prefer plugins/ if it has actual plugin directories
+    if plugins_path.exists():
+        try:
+            has_plugins = any(
+                p for p in plugins_path.iterdir()
+                if p.is_dir() and not p.name.startswith('.')
+            )
+            if has_plugins:
+                return plugins_path
+        except PermissionError:
+            pass
+    if plugin_repos_path.exists():
+        return plugin_repos_path
+    return plugins_path
 
 
 @pytest.fixture
-def mock_display_manager():
+def mock_display_manager() -> Any:
     """Create a mock DisplayManager for plugin tests."""
     mock = MagicMock()
     mock.width = 128
@@ -44,7 +64,7 @@ def mock_display_manager():
 
 
 @pytest.fixture
-def mock_cache_manager():
+def mock_cache_manager() -> Any:
     """Create a mock CacheManager for plugin tests."""
     mock = MagicMock()
     mock._memory_cache = {}
@@ -68,7 +88,7 @@ def mock_cache_manager():
 
 
 @pytest.fixture
-def mock_plugin_manager():
+def mock_plugin_manager() -> Any:
     """Create a mock PluginManager for plugin tests."""
     mock = MagicMock()
     mock.plugins = {}
@@ -77,7 +97,7 @@ def mock_plugin_manager():
 
 
 @pytest.fixture
-def base_plugin_config():
+def base_plugin_config() -> Dict[str, Any]:
     """Base configuration for plugins."""
     return {
         'enabled': True,
@@ -102,3 +122,10 @@ def get_plugin_config_schema(plugin_id: str, plugins_dir: Path) -> Dict[str, Any
         with open(schema_path, 'r') as f:
             return json.load(f)
     return None
+
+
+@pytest.fixture
+def visual_display_manager() -> Any:
+    """Create a VisualTestDisplayManager that renders real pixels for visual testing."""
+    from src.plugin_system.testing import VisualTestDisplayManager
+    return VisualTestDisplayManager(width=128, height=32)