feat: entity relationship refactor — notification trackers, command system, chat actions

Rework entity schema: rename Tracker→NotificationTracker, add CommandConfig/
CommandTracker/CommandTrackerListener entities for decoupled command handling.
Commands now resolve through CommandTracker→CommandConfig instead of
TelegramBot.commands_config. Smart ref-counted bot polling based on active
listeners. Add chat_action to telegram targets. Full frontend CRUD pages
for command configs and command trackers. Idempotent SQLite migrations.

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

frontend/src/lib/i18n/en.json

@@ -6,11 +6,13 @@
 	"nav": {
 		"dashboard": "Dashboard",
 		"providers": "Providers",
-		"trackers": "Trackers",
+		"notificationTrackers": "Notif. Trackers",
 		"trackingConfigs": "Tracking",
 		"templateConfigs": "Templates",
 		"telegramBots": "Bots",
 		"targets": "Targets",
+		"commandConfigs": "Cmd Configs",
+		"commandTrackers": "Cmd Trackers",
 		"users": "Users",
 		"settings": "Settings",
 		"logout": "Logout"
@@ -93,8 +95,8 @@
 		"testAndSave": "Test & Save",
 		"saveWithoutTest": "Save without testing"
 	},
-	"trackers": {
-		"title": "Trackers",
+	"notificationTracker": {
+		"title": "Notification Trackers",
 		"description": "Monitor albums for changes",
 		"newTracker": "New Tracker",
 		"cancel": "Cancel",
@@ -198,7 +200,9 @@
 		"maxAssetSize": "Max asset size (MB)",
 		"videoWarning": "Video size warning",
 		"disableUrlPreview": "Disable link previews",
-		"sendLargeAsDocuments": "Send large photos as documents"
+		"sendLargeAsDocuments": "Send large photos as documents",
+		"chatAction": "Chat action",
+		"chatActionNone": "None (no action)"
 	},
 	"users": {
 		"title": "Users",
@@ -474,6 +478,47 @@
 		"botLocale": "Language for command descriptions in Telegram's menu and bot response messages.",
 		"rateLimits": "Cooldown in seconds between uses of each command category per chat. 0 = no limit."
 	},
+	"commandConfig": {
+		"title": "Command Configs",
+		"description": "Define command settings for Telegram bot interactions",
+		"newConfig": "New Config",
+		"name": "Name",
+		"namePlaceholder": "Default commands",
+		"providerType": "Provider Type",
+		"enabledCommands": "Enabled Commands",
+		"locale": "Locale",
+		"responseMode": "Response Mode",
+		"modeMedia": "Media (photos)",
+		"modeText": "Text only",
+		"defaultCount": "Default Count",
+		"rateLimits": "Rate Limits",
+		"searchCooldown": "Search cooldown (s)",
+		"defaultCooldown": "Default cooldown (s)",
+		"noConfigs": "No command configs yet.",
+		"confirmDelete": "Delete this command config?",
+		"commands": "commands"
+	},
+	"commandTracker": {
+		"title": "Command Trackers",
+		"description": "Manage command trackers and their listeners",
+		"newTracker": "New Tracker",
+		"name": "Name",
+		"namePlaceholder": "Family commands",
+		"provider": "Provider",
+		"selectProvider": "Select provider...",
+		"commandConfig": "Command Config",
+		"selectCommandConfig": "Select command config...",
+		"listeners": "Listeners",
+		"addListener": "Add Listener",
+		"removeListener": "Remove",
+		"noTrackers": "No command trackers yet.",
+		"confirmDelete": "Delete this command tracker?",
+		"enabled": "Enabled",
+		"disabled": "Disabled",
+		"noListeners": "No listeners attached.",
+		"selectBot": "Select bot...",
+		"listenerType": "telegram_bot"
+	},
 	"snackbar": {
 		"showDetails": "Show details",
 		"hideDetails": "Hide details"
@@ -504,7 +549,16 @@
 		"commandsSynced": "Commands synced to Telegram",
 		"targetLinked": "Target linked",
 		"targetUnlinked": "Target unlinked",
-		"botUpdated": "Bot updated"
+		"botUpdated": "Bot updated",
+		"commandConfigSaved": "Command config saved",
+		"commandConfigDeleted": "Command config deleted",
+		"commandTrackerCreated": "Command tracker created",
+		"commandTrackerUpdated": "Command tracker updated",
+		"commandTrackerDeleted": "Command tracker deleted",
+		"commandTrackerEnabled": "Command tracker enabled",
+		"commandTrackerDisabled": "Command tracker disabled",
+		"listenerAdded": "Listener added",
+		"listenerRemoved": "Listener removed"
 	},
 	"common": {
 		"loading": "Loading...",