feat: mute screenshare audio independently + fix CI lint/prettier

- Add screenshareAudioMuted state to CallControlState and CallControl
- setSound() now preserves screenshare audio mute when un-deafening
- Add toggleScreenshareAudio() targeting audio[data-lk-source="screen_share_audio"]
- Add ScreenshareAudioButton (volume icon, warns when muted) to controls bar
- Fix unused prevScreenshare variable (ESLint error from prior commit)
- Run Prettier on Controls.tsx and CallControl.ts (CI formatting failures)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/plugins/call/CallControl.ts

@@ -93,6 +93,10 @@ export class CallControl extends EventEmitter implements CallControlState {
     return this.state.spotlight;
   }
 
+  public get screenshareAudioMuted(): boolean {
+    return this.state.screenshareAudioMuted;
+  }
+
   public async applyState() {
     await this.setMediaState({
       audio_enabled: this.microphone,
@@ -145,11 +149,24 @@ export class CallControl extends EventEmitter implements CallControlState {
     const callDocument = this.iframe.contentDocument ?? this.iframe.contentWindow?.document;
     if (callDocument) {
       callDocument.querySelectorAll('audio').forEach((el) => {
-        el.muted = !sound;
+        const isScreenshareAudio = el.getAttribute('data-lk-source') === 'screen_share_audio';
+        el.muted = !sound || (isScreenshareAudio && this.screenshareAudioMuted);
       });
     }
   }
 
+  private applyScreenshareAudioMuted(): void {
+    if (!this.sound) return;
+    const callDocument = this.iframe.contentDocument ?? this.iframe.contentWindow?.document;
+    if (callDocument) {
+      callDocument
+        .querySelectorAll<HTMLAudioElement>('audio[data-lk-source="screen_share_audio"]')
+        .forEach((el) => {
+          el.muted = this.screenshareAudioMuted;
+        });
+    }
+  }
+
   public onMediaState(evt: CustomEvent<ElementMediaStateDetail>) {
     const { data } = evt.detail;
     if (!data) return;
@@ -160,6 +177,7 @@ export class CallControl extends EventEmitter implements CallControlState {
       this.sound,
       this.screenshare,
       this.spotlight,
+      this.screenshareAudioMuted,
     );
 
     this.state = state;
@@ -171,8 +189,6 @@ export class CallControl extends EventEmitter implements CallControlState {
   }
 
   public onControlMutation() {
-    const prevScreenshare = this.screenshare;
-
     const screenshare: boolean = this.screenshareButton?.getAttribute('data-kind') === 'primary';
     const spotlight: boolean = this.spotlightButton?.checked ?? false;
 
@@ -182,9 +198,9 @@ export class CallControl extends EventEmitter implements CallControlState {
       this.sound,
       screenshare,
       spotlight,
+      this.screenshareAudioMuted,
     );
     this.emitStateUpdate();
-
   }
 
   public setMicrophone(enabled: boolean) {
@@ -215,6 +231,8 @@ export class CallControl extends EventEmitter implements CallControlState {
     const sound = !this.sound;
 
     this.setSound(sound);
+    // After un-deafening, re-apply screenshare audio mute if active
+    if (sound) this.applyScreenshareAudioMuted();
 
     const state = new CallControlState(
       this.microphone,
@@ -222,6 +240,7 @@ export class CallControl extends EventEmitter implements CallControlState {
       sound,
       this.screenshare,
       this.spotlight,
+      this.screenshareAudioMuted,
     );
     this.state = state;
     this.emitStateUpdate();
@@ -231,6 +250,20 @@ export class CallControl extends EventEmitter implements CallControlState {
     }
   }
 
+  public toggleScreenshareAudio() {
+    const screenshareAudioMuted = !this.screenshareAudioMuted;
+    this.state = new CallControlState(
+      this.microphone,
+      this.video,
+      this.sound,
+      this.screenshare,
+      this.spotlight,
+      screenshareAudioMuted,
+    );
+    this.emitStateUpdate();
+    this.applyScreenshareAudioMuted();
+  }
+
   public toggleScreenshare() {
     this.screenshareButton?.click();
   }

src/app/plugins/call/CallControlState.ts

@@ -9,17 +9,21 @@ export class CallControlState {
 
   public readonly spotlight: boolean;
 
+  public readonly screenshareAudioMuted: boolean;
+
   constructor(
     microphone: boolean,
     video: boolean,
     sound: boolean,
     screenshare = false,
     spotlight = false,
+    screenshareAudioMuted = false,
   ) {
     this.microphone = microphone;
     this.video = video;
     this.sound = sound;
     this.screenshare = screenshare;
     this.spotlight = spotlight;
+    this.screenshareAudioMuted = screenshareAudioMuted;
   }
 }