fix: persist status message and timezone across reconnects

Status message: Synapse clears status_msg when a user goes offline/reconnects.
Fix by caching to localStorage and re-sending on setOnline(). The sync
effect no longer overwrites the local value with an empty server event.

Timezone: PUT /profile/{userId}/m.tz is MSC1769 (unstable) and not
supported by standard Synapse — save/load silently fails. Fix by using
Matrix account data (im.lotus.timezone) instead, which is fully
supported. Own profile falls back to account data; other users still
try the m.tz profile endpoint (for federated servers that support it).

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

src/app/features/settings/account/Profile.tsx

@@ -317,6 +317,7 @@ function ProfileDisplayName({ profile, userId }: ProfileProps) {
 }
 
 const STATUS_EXPIRY_KEY = (id: string) => `lotus-status-expiry-${id}`;
+const STATUS_MSG_KEY = (id: string) => `lotus-status-msg-${id}`;
 
 const CLEAR_AFTER_OPTIONS = [
   { label: 'Never', value: '0' },
@@ -344,7 +345,9 @@ function ProfileStatus() {
   const userId = mx.getUserId()!;
   const presence = useUserPresence(userId);
 
-  const [statusMsg, setStatusMsg] = useState<string>(presence?.status ?? '');
+  const [statusMsg, setStatusMsg] = useState<string>(
+    presence?.status ?? localStorage.getItem(STATUS_MSG_KEY(userId)) ?? '',
+  );
   const [clearAfter, setClearAfter] = useState('0');
   const [emojiAnchor, setEmojiAnchor] = useState<RectCords>();
 
@@ -354,16 +357,22 @@ function ProfileStatus() {
     return stored ? parseInt(stored, 10) : 0;
   });
 
-  // Sync input when another device changes the status
+  // Sync input when another device changes the status.
+  // Only update if the server actually has a value — ignore empty sync events
+  // caused by Synapse clearing status_msg on reconnect.
   useEffect(() => {
-    setStatusMsg(presence?.status ?? '');
-  }, [presence?.status]);
+    if (presence?.status) {
+      setStatusMsg(presence.status);
+      localStorage.setItem(STATUS_MSG_KEY(userId), presence.status);
+    }
+  }, [presence?.status, userId]);
 
   // Drive the auto-clear timer off expiryTs so re-saving cancels the old timer
   useEffect(() => {
     if (!expiryTs) return undefined;
     const remaining = expiryTs - Date.now();
     const clearStatus = () => {
+      localStorage.removeItem(STATUS_MSG_KEY(userId));
       localStorage.removeItem(STATUS_EXPIRY_KEY(userId));
       setExpiryTs(0);
       mx.setPresence({ presence: 'online', status_msg: '' }).catch(() => undefined);
@@ -403,6 +412,12 @@ function ProfileStatus() {
     const msg = statusMsg.trim();
     saveStatus(msg).catch(() => undefined);
 
+    if (msg) {
+      localStorage.setItem(STATUS_MSG_KEY(userId), msg);
+    } else {
+      localStorage.removeItem(STATUS_MSG_KEY(userId));
+    }
+
     const delayMs = getMsFromOption(clearAfter);
     if (msg && delayMs > 0) {
       const ts = Date.now() + delayMs;
@@ -416,6 +431,7 @@ function ProfileStatus() {
 
   const handleClear = () => {
     setStatusMsg('');
+    localStorage.removeItem(STATUS_MSG_KEY(userId));
     localStorage.removeItem(STATUS_EXPIRY_KEY(userId));
     setExpiryTs(0);
     mx.setPresence({ presence: 'online', status_msg: '' }).catch(() => undefined);
@@ -722,30 +738,34 @@ function ProfileTimezone() {
   const [savedTimezone, setSavedTimezone] = useState<string>('');
 
   useEffect(() => {
+    const cached = mx.getAccountData('im.lotus.timezone' as any)?.getContent<{ timezone: string }>();
+    if (cached?.timezone) {
+      setTimezone(cached.timezone);
+      setSavedTimezone(cached.timezone);
+    }
+    // Also fetch from server in case account data hasn't synced yet
     mx.http
-      .authedRequest<{ 'm.tz': string }>(Method.Get, `/profile/${encodeURIComponent(userId)}/m.tz`)
+      .authedRequest<{ timezone: string }>(
+        Method.Get,
+        `/user/${encodeURIComponent(userId)}/account_data/im.lotus.timezone`,
+      )
       .then((res) => {
-        const val = res['m.tz'] ?? '';
+        const val = res.timezone ?? '';
         setTimezone(val);
         setSavedTimezone(val);
       })
       .catch(() => {
-        setTimezone('');
-        setSavedTimezone('');
+        /* no stored timezone yet */
       });
   }, [mx, userId]);
 
   const [saveState, saveTimezone] = useAsyncCallback(
     useCallback(
       (value: string) =>
-        mx.http
-          .authedRequest(Method.Put, `/profile/${encodeURIComponent(userId)}/m.tz`, undefined, {
-            'm.tz': value,
-          })
-          .then(() => {
-            setSavedTimezone(value);
-          }),
-      [mx, userId],
+        (mx as any).setAccountData('im.lotus.timezone', { timezone: value }).then(() => {
+          setSavedTimezone(value);
+        }),
+      [mx],
     ),
   );
   const saving = saveState.status === AsyncStatus.Loading;