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/app/features/room-nav/RoomNavItem.tsx

@@ -214,6 +214,7 @@ const RoomNavItemMenu = forwardRef<HTMLDivElement, RoomNavItemMenuProps>(
     const space = useSpaceOptionally();
 
     const [invitePrompt, setInvitePrompt] = useState(false);
+    const isServerNotice = room.getType() === 'm.server_notice';
 
     const handleMarkAsRead = () => {
       markAsRead(mx, room.roomId, hideActivity);
@@ -320,16 +321,18 @@ const RoomNavItemMenu = forwardRef<HTMLDivElement, RoomNavItemMenuProps>(
               Rename for me…
             </Text>
           </MenuItem>
-          <MenuItem
-            onClick={handleRoomSettings}
-            size="300"
-            after={<Icon size="100" src={Icons.Setting} />}
-            radii="300"
-          >
-            <Text style={{ flexGrow: 1 }} as="span" size="T300" truncate>
-              Room Settings
-            </Text>
-          </MenuItem>
+          {!isServerNotice && (
+            <MenuItem
+              onClick={handleRoomSettings}
+              size="300"
+              after={<Icon size="100" src={Icons.Setting} />}
+              radii="300"
+            >
+              <Text style={{ flexGrow: 1 }} as="span" size="T300" truncate>
+                Room Settings
+              </Text>
+            </MenuItem>
+          )}
         </Box>
         <Line variant="Surface" size="300" />
         <Box direction="Column" gap="100" style={{ padding: config.space.S100 }}>