feat: add Planka service provider with full notification and command support

Webhook-based provider for Planka (self-hosted Kanban board) with:
- 15 event types (cards, boards, lists, comments, tasks, attachments, labels)
- Bearer token webhook authentication
- Async API client for boards/cards/lists
- 30 notification templates (en/ru) + 26 command templates (en/ru)
- Bot commands: /status, /boards, /cards, /lists
- Default tracking config, template config, command config seeded on startup
- DB migration for 15 new tracking_config columns
- Frontend: provider config UI with auto-name, Planka-specific hints
- Frontend: tracking config event toggles for all 15 Planka events

packages/server/src/notify_bridge_server/commands/registry.py

@@ -9,6 +9,8 @@ _RATE_CATEGORY: dict[str, str] = {
     "place": "search", "favorites": "search", "people": "search",
     # Gitea (API calls share a category)
     "repos": "api", "issues": "api", "prs": "api", "commits": "api",
+    # Planka (API calls share a category)
+    "boards": "api", "cards": "api", "lists": "api",
 }