fix: P0 post-deploy bug fixes from live testing

- EditHistoryModal: use raw fetch with /_matrix/client/v1/ path for
  relations API — Synapse only supports relations at v1, not v3 (fixes
  Sentry JAVASCRIPT-REACT-K / 404 error)
- RoomViewHeader: remove useReportRoomSupported spec-version gate —
  Synapse 1.114+ has the endpoint but only advertises spec v1.12;
  button now always shows for non-creator, non-server-notice rooms
- ReportRoomModal: handle M_UNRECOGNIZED/404 with "not supported by
  your homeserver" message
- RoomNavItem: add isServerNotice guard to Room Settings in sidebar
  context menu (was only guarded in header three-dots menu)
- initMatrix: bump setMaxListeners from 50 → 150 to prevent
  MaxListenersExceededWarning with large room lists
- RoomProfile: save topic with formatted_body + format when markdown
  syntax is detected; add markdown hint below topic textarea

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

src/client/initMatrix.ts

@@ -47,9 +47,8 @@ export const initClient = async (session: Session): Promise<MatrixClient> => {
   }
   await mx.initRustCrypto();
 
-  mx.setMaxListeners(50);
-  // Each RoomNavItem subscribes to session_started/session_ended; one listener per visible room.
-  mx.matrixRTC.setMaxListeners(100);
+  mx.setMaxListeners(150);
+  mx.matrixRTC.setMaxListeners(150);
 
   return mx;
 };