- Removed the unused `serve_html` handler and its import.
- Added a fallback static file service that serves `index.html` for any unmatched path, enabling proper SPA routing.
- Reordered service registration to place the fallback before the explicit index route.
- Cleaned up redundant blank lines and imports in `mod.rs`.
**Client-side (chat.js) updates**
- Renamed the message input variable from `input` to `messageInputEl` for clarity.
- Introduced `pendingContextChange` placeholder for future context handling.
- Switched initialization event from `document 'ready'` to `window 'load'`.
- Updated DOM element assignments and focus calls to use the new variable name.
- Removed unused sidebar auto‑close logic and obsolete session loading functions (`loadSessions`, `loadSessionHistory`).
- Minor refactoring and comment adjustments to improve readability and eliminate dead code.