✨(frontend) add hook to manage noise reduction processor toggling

Create concise hook that listens to audio track status and user noise
reduction preference to automatically handle processor state changes.

Note: Logging could be improved in future iterations.

src/frontend/src/features/rooms/livekit/hooks/useNoiseReduction.ts

@@ -0,0 +1,30 @@
+import { useEffect } from 'react'
+import { Track } from 'livekit-client'
+import { useRoomContext } from '@livekit/components-react'
+import { RnnNoiseProcessor } from '../processors/RnnNoiseProcessor'
+import { usePersistentUserChoices } from './usePersistentUserChoices'
+
+export const useNoiseReduction = () => {
+  const room = useRoomContext()
+
+  const {
+    userChoices: { noiseReductionEnabled },
+  } = usePersistentUserChoices()
+
+  const audioTrack = room.localParticipant.getTrackPublication(
+    Track.Source.Microphone
+  )?.audioTrack
+
+  useEffect(() => {
+    if (!audioTrack) return
+
+    const processor = audioTrack?.getProcessor()
+
+    if (noiseReductionEnabled && !processor) {
+      const rnnNoiseProcessor = new RnnNoiseProcessor()
+      audioTrack.setProcessor(rnnNoiseProcessor)
+    } else if (!noiseReductionEnabled && processor) {
+      audioTrack.stopProcessor()
+    }
+  }, [audioTrack, noiseReductionEnabled])
+}

src/frontend/src/features/rooms/livekit/prefabs/VideoConference.tsx

@@ -31,6 +31,7 @@ import { useSidePanel } from '../hooks/useSidePanel'
 import { RecordingStateToast } from '@/features/recording'
 import { ScreenShareErrorModal } from '../components/ScreenShareErrorModal'
 import { useConnectionObserver } from '../hooks/useConnectionObserver'
+import { useNoiseReduction } from '../hooks/useNoiseReduction'
 
 const LayoutWrapper = styled(
   'div',
@@ -87,6 +88,8 @@ export function VideoConference({ ...props }: VideoConferenceProps) {
 
   const layoutContext = useCreateLayoutContext()
 
+  useNoiseReduction()
+
   const screenShareTracks = tracks
     .filter(isTrackReference)
     .filter((track) => track.publication.source === Track.Source.ScreenShare)