♻️ refactor(web): migrate React modules from .js to .jsx and align entrypoint

- Rename React components/pages/utilities that contain JSX to `.jsx` across `web/src`
- Update import paths and re-exports to match new `.jsx` extensions
- Fix Vite entry by switching `web/index.html` from `/src/index.js` to `/src/index.jsx`
- Verified remaining `.js` files are plain JS (hooks/helpers/constants) and do not require JSX
- No runtime behavior changes; extension and reference alignment only

Context: Resolves the Vite pre-transform error caused by the stale `/src/index.js` entry after migrating to `.jsx`.

web/src/components/layout/HeaderBar.js

@@ -17,4 +17,4 @@ along with this program. If not, see <https://www.gnu.org/licenses/>.
 For commercial licensing, please contact support@quantumnous.com
 */
 
-export { default } from './HeaderBar/index.js';
+export { default } from './HeaderBar/index';