fix: remove setDisplayMediaRequestHandler to let restrictOwnAudio work natively

The custom screen share picker intercepted getDisplayMedia() and created
a raw loopback stream, bypassing Chromium's constraint pipeline entirely.
restrictOwnAudio was silently discarded. Removing the handler lets
Chromium 144's native getDisplayMedia run end-to-end with restrictOwnAudio
applied, eliminating the audio feedback loop in the desktop app.

packages/web/src/App.tsx

@@ -5,7 +5,6 @@ import { RegisterPage } from './components/auth/RegisterPage';
 import { AppLayout } from './components/layout/AppLayout';
 import { JoinPage } from './components/JoinPage';
 import { SwAutoUpdate } from './components/ui/SwUpdatePrompt';
-import { ScreenSharePicker } from './components/voice/ScreenSharePicker';
 import { useAuthStore } from './stores/authStore';
 import { isElectron } from './platform/platform';
 
@@ -39,7 +38,6 @@ export function App() {
       </>}
       <div className={showTitleBar ? 'flex-1 min-h-0' : 'contents'}>
         <SwAutoUpdate />
-        <ScreenSharePicker />
         <Routes>
           <Route
             path="/login"