fix(web): widget cache-busting, dead frontend code, and dependency pins (#656)

- Plugin-supplied widgets load as /static/plugin-widgets/...js?v=<plugin
  version>, so an update isn't hidden behind the year-long immutable cache.
- Fire-and-forget loadInstalledPlugins() calls catch the rejection it has
  already reported, so the global handler no longer adds a second toast.
- Timezone picker renders again when the General partial is re-injected.
- Remove dead code: executePluginAction's six plugin-id fallbacks and
  [DEBUG] logging, window.currentPluginConfig and every read of it, the
  file-upload JSON delete branch, unused PluginAPI / PluginInstallManager /
  PluginStateManager helpers, loadPluginWidgetsFromManifest, the stale
  install_manager.js and LEDVisibility fallbacks, error_handler.js's global
  escapeHtml, 13 unused CSS rules, and stale comments/no-op returns.
- pytz < 2027, psutil < 7 in requirements-test.txt, pytest-cov < 8.
- Pin anthropics/claude-code-action to the commit v1 resolves to.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

web_interface/static/v3/js/plugins/state_manager.js

@@ -9,12 +9,7 @@ const PluginStateManager = {
      * Installed plugins state.
      */
     installedPlugins: [],
-    
-    /**
-     * Current plugin configuration state.
-     */
-    currentConfig: null,
-    
+
     /**
      * Load installed plugins.
      * 
@@ -32,83 +27,6 @@ const PluginStateManager = {
             }
             throw error;
         }
-    },
-    
-    /**
-     * Get plugin by ID.
-     * 
-     * @param {string} pluginId - Plugin identifier
-     * @returns {Object|null} Plugin object or null
-     */
-    getPlugin(pluginId) {
-        return this.installedPlugins.find(p => p.id === pluginId) || null;
-    },
-    
-    /**
-     * Update plugin state.
-     * 
-     * @param {string} pluginId - Plugin identifier
-     * @param {Object} updates - State updates
-     */
-    updatePlugin(pluginId, updates) {
-        const plugin = this.getPlugin(pluginId);
-        if (plugin) {
-            Object.assign(plugin, updates);
-        }
-    },
-    
-    /**
-     * Set plugin enabled state.
-     * 
-     * @param {string} pluginId - Plugin identifier
-     * @param {boolean} enabled - Whether plugin is enabled
-     */
-    setPluginEnabled(pluginId, enabled) {
-        this.updatePlugin(pluginId, { enabled });
-    },
-    
-    /**
-     * Get current plugin configuration.
-     * 
-     * @param {string} pluginId - Plugin identifier
-     * @returns {Promise<Object>} Plugin configuration
-     */
-    async getPluginConfig(pluginId) {
-        try {
-            const config = await window.PluginAPI.getPluginConfig(pluginId);
-            this.currentConfig = { pluginId, config };
-            return config;
-        } catch (error) {
-            if (window.errorHandler) {
-                window.errorHandler.displayError(error, `Failed to load config for ${pluginId}`);
-            }
-            throw error;
-        }
-    },
-    
-    /**
-     * Save plugin configuration.
-     * 
-     * @param {string} pluginId - Plugin identifier
-     * @param {Object} config - Configuration data
-     * @returns {Promise<Object>} Save result
-     */
-    async savePluginConfig(pluginId, config) {
-        try {
-            const result = await window.PluginAPI.savePluginConfig(pluginId, config);
-            
-            // Update local state
-            if (this.currentConfig && this.currentConfig.pluginId === pluginId) {
-                this.currentConfig.config = config;
-            }
-            
-            return result;
-        } catch (error) {
-            if (window.errorHandler) {
-                window.errorHandler.displayError(error, `Failed to save config for ${pluginId}`);
-            }
-            throw error;
-        }
     }
 };