fix: resolve Copilot review comments on PR SableClient#564

- useTimelineEventRenderer.tsx: Use Math.max(thread.length, replyEvents.length) to avoid undercounting replies when only a subset of events is loaded locally.
- ThreadBrowser.tsx: Use Math.max(thread.length, localReplyCount) to show correct total even for threads whose timeline hasn't been fully paginated.
- ThreadDrawer.tsx: Align showClientUrlPreview logic with RoomTimeline: require both clientUrlPreview AND encClientUrlPreview in encrypted rooms.
- useMessageEdit.ts: Minor wording: 'never stales' → 'never goes stale'.

Author: Just-Insane

src/app/features/room/ThreadBrowser.tsx

@@ -153,7 +153,7 @@ function ThreadPreview({ room, thread, onClick }: ThreadPreviewProps) {
   const localReplyCount = thread.events.filter(
     (ev: MatrixEvent) => ev.getId() !== thread.id && !reactionOrEditEvent(ev)
   ).length;
-  const replyCount = localReplyCount > 0 ? localReplyCount : thread.length;
+  const replyCount = Math.max(thread.length ?? 0, localReplyCount);
 
   const lastReply = thread.events
     .filter((ev: MatrixEvent) => ev.getId() !== thread.id && !reactionOrEditEvent(ev))

src/app/features/room/ThreadDrawer.tsx

@@ -132,7 +132,7 @@ export function ThreadDrawer({ room, threadRootId, onClose, overlay }: ThreadDra
   const [hideMemberInReadOnly] = useSetting(settingsAtom, 'hideMembershipInReadOnly');
   const showUrlPreview = room.hasEncryptionStateEvent() ? encUrlPreview : urlPreview;
   const showClientUrlPreview = room.hasEncryptionStateEvent()
-    ? encClientUrlPreview
+    ? clientUrlPreview && encClientUrlPreview
     : clientUrlPreview;
 
   // Memoized parsing options

src/app/hooks/timeline/useTimelineEventRenderer.tsx

@@ -148,7 +148,7 @@ function ThreadReplyChip({
 
   if (!thread) return null;
 
-  const replyCount = replyEvents.length || (thread.length ?? 0);
+  const replyCount = Math.max(thread.length ?? 0, replyEvents.length);
   if (replyCount === 0) return null;
 
   const uniqueSenders: string[] = [];

src/app/hooks/useMessageEdit.ts

@@ -22,7 +22,7 @@ export function useMessageEdit(
 ): { editId: string | undefined; handleEdit: (editId?: string) => void } {
   const [editId, setEditId] = useState<string | undefined>(undefined);
 
-  // Use refs so the callback never stales on options changes.
+  // Use refs so the callback never goes stale on options changes.
   const aliveRef = useRef(options?.alive);
   aliveRef.current = options?.alive;
   const onResetRef = useRef(options?.onReset);