feat: add Citations and WatchlistChat components, integrate with API

- Implemented Citations component to display citation data.
- Created WatchlistDrawer and ChatSidebar components for managing watchlists and AI chat functionality.
- Integrated API calls for watchlist management and chat interactions.
- Updated index.tsx to include new components in the main application layout.
- Added API client in lib/api.ts for structured API interactions.
- Developed Alerts, Dashboard, Portfolio, Routines, Screener, and Report pages with relevant data fetching and UI components.
- Introduced styles in tokens.css for consistent theming across the application.
- Configured TypeScript and Vite for project setup and development.

backend/tests/fixtures/filings_bbca.json

@@ -0,0 +1,16 @@
+{
+ "results": [
+  {
+   "title": "Direksi beli saham BBCA",
+   "symbol": "BBCA",
+   "timestamp": "2026-09-10T10:00:00Z",
+   "transaction_type": "buy",
+   "holder_type": "insider",
+   "holder_name": "Direktur X",
+   "amount_transaction": 500000,
+   "price": 9850,
+   "transaction_value": 4925000000,
+   "source": "https://idx.example/f"
+  }
+ ]
+}