fix(calls): Reject sends the decline to the ring notification (#313)

handleReject related the MSC4310 decline to the caller's call.member event
(the notification's reference), but MSC4310 and Element Call match a
decline against the rtc.notification event itself, so the caller kept
"Calling…" for the full 90 s after being told "Declined", and declines
from other clients (correctly referencing the notification) didn't stop
Lotus ringing on other devices.

- The incoming call keeps the notification's own event id; Reject relates
  the decline to it.
- The "declined on another device" dismissal and declinedRing accept
  either id (older Lotus builds referenced the membership).
- The missed-call line is skipped for a call we declined.

Verified headless (DM, Bob rings, Reject): the decline used to reference
the membership; it now references the notification. Unit test added.

Fixes #313

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

src/app/features/room/RoomTimeline.tsx

@@ -138,7 +138,7 @@ import { useMediaAuthentication } from '../../hooks/useMediaAuthentication';
 import { useIgnoredUsers } from '../../hooks/useIgnoredUsers';
 import { useImagePackRooms } from '../../hooks/useImagePackRooms';
 import { useIsDirectRoom } from '../../hooks/useRoom';
-import { isRingableRoom } from '../../utils/callRing';
+import { declinedRing, isRingableRoom } from '../../utils/callRing';
 import { useOpenUserRoomProfile } from '../../state/hooks/userRoomProfile';
 import { useSpaceOptionally } from '../../hooks/useSpace';
 import { useRoomCreators } from '../../hooks/useRoomCreators';
@@ -2037,6 +2037,9 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
         // Same rule as ringing: no "Missed call" in voice rooms or space
         // channels, where starting a call is just joining the channel.
         if (!isRingableRoom(room, direct)) return null;
+        // [Gitea #313] A call we declined isn't a missed call.
+        const ringRef = mEvent.getRelation()?.event_id;
+        if (declinedRing(room, [mEventId, ringRef], mx.getSafeUserId())) return null;
         const content = mEvent.getContent();
         const mention =
           content['m.mentions']?.room ||