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/close_idx.json

@@ -0,0 +1,18 @@
+{
+ "results": [
+  {
+   "symbol": "BBCA.JK",
+   "date": "2026-09-11",
+   "close": 9950
+  },
+  {
+   "symbol": "BBRI.JK",
+   "date": "2026-09-11",
+   "close": 4200
+  }
+ ],
+ "pagination": {
+  "total": 2,
+  "count": 2
+ }
+}