chore: merge v4.12.1 — security, calling, editor, media fixes

Key v4.12.1 changes merged:
- Security: sanitize-html updated to v2.17.4
- Calling: video calls in DMs/rooms, user avatars during calls, right-click to start
- Calling: IncomingCallListener with ring sound and answer/reject UI
- Editor: list crash fixes (Firefox + empty headings), codeblock filename support
- Media: URL preview hover state, keyboard nav, click-to-open, OGG audio support
- Date: ISO 8601 (YYYY-MM-DD) date format option
- Misc: stable mutual rooms endpoint, Android notification crash fix

Lotus customisations preserved:
- PiP drag/resize, DM call ring notification, PTT, GIF picker, noise suppression
- Poll voting, message forwarding, image captions, location sharing
- Lotus Terminal design theme

src/app/hooks/useCallEmbed.ts

@@ -52,7 +52,7 @@ export const createCallEmbed = (
   const ongoing =
     MatrixRTCSession.sessionMembershipsForRoom(room, rtcSession.sessionDescription).length > 0;
 
-  const intent = CallEmbed.getIntent(dm, ongoing);
+  const intent = CallEmbed.getIntent(dm, ongoing, pref?.video);
   const initialAudio = forceAudioOff ? false : (pref?.microphone ?? true);
   const initialVideo = pref?.video ?? false;
   const widget = CallEmbed.getWidget(mx, room, intent, themeKind, noiseSuppression, initialAudio, initialVideo);
@@ -109,6 +109,7 @@ export const useCallJoined = (embed?: CallEmbed): boolean => {
 
 export const useCallHangupEvent = (embed: CallEmbed, callback: () => void) => {
   useClientWidgetApiEvent(embed.call, ElementWidgetActions.HangupCall, callback);
+  useClientWidgetApiEvent(embed.call, ElementWidgetActions.Close, callback);
 };
 
 export const useCallMemberSoundSync = (embed: CallEmbed) => {