fix(call): one-row call bar on phones; screenshare-audio mute only when useful (#265, #277)

#265: in the compact layout (phones, narrow windows) the control bar
stacked into four rows (~330px, 40% of a portrait phone). It is now one
row: mic, deafen, camera, chat, soundboard, More and an icon-only End.
Screenshare, its audio mute and fullscreen move into More; Share Screen
is only offered where getDisplayMedia exists. (The self-view comes from
the fork, lotus.27.)

#277: "Mute Screenshare Audio" showed whenever screensharing was allowed,
as a speaker icon that did nothing. It now shows while the fork reports
remote screenshare audio (io.lotus.screenshare_audio_state), or while it
is muted, so a hidden mute cannot silence the next share.

Fixes #265
Fixes #277

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017PCb59uY3UKqDqt7B6hzd5

src/app/plugins/call/CallEmbed.ts

@@ -465,6 +465,12 @@ export class CallEmbed {
         this.control.onAudioOutputState((evt.detail as { data?: unknown } | undefined)?.data);
       }),
     );
+    // [Gitea #277] Remote screenshare audio being received, or not.
+    this.disposables.push(
+      this.listenAction('io.lotus.screenshare_audio_state', (evt) => {
+        this.control.onScreenshareAudioState((evt.detail as { data?: unknown } | undefined)?.data);
+      }),
+    );
     // [Gitea #43] PTT / deafen keys pressed while focus is inside the frame.
     this.disposables.push(
       this.listenAction('io.lotus.hotkey', (evt) => {