refactor(chat-switch): drop redundant id-change reset effect

apps/desktop/src/pages/ConversationPage.tsx

@@ -94,18 +94,18 @@ type VirtuosoRow =
 // change on every parent render.
 const EMPTY_REACTIONS: AggregatedReaction[] = [];
 
-// Per-conversation scroll memory. Module-scoped so it survives re-mounts
-// of ConversationPage when the route param (`id`) changes — switching
-// chats unmounts/remounts the page in our router setup. Session-only
-// (lost on reload, like Discord). The `stickToBottom` flag is preserved
-// alongside the topmost-visible row index so a chat the user left at the
-// bottom keeps auto-following new messages when they return; a chat
-// scrolled up returns to roughly the same row the user was reading.
+// Per-conversation scroll memory. Module-scoped so it survives the
+// per-id remount of ConversationPage (see `ConversationRoute` in
+// App.tsx). Session-only (lost on reload, like Discord). The
+// `stickToBottom` flag is preserved alongside the topmost-visible row
+// index so a chat the user left at the bottom keeps auto-following new
+// messages when they return; a chat scrolled up returns to roughly the
+// same row the user was reading.
 //
 // We track the topmost-visible row index rather than a pixel `scrollTop`
 // because `react-virtuoso` virtualizes the list — the underlying scroll
 // element's pixel offset depends on dynamically-measured row heights and
-// is not stable across re-mounts. Using a row index restores the user's
+// is not stable across remounts. Using a row index restores the user's
 // reading position even if some rows above re-render at different heights.
 const scrollPositions = new Map<string, { topmostIndex: number; stickToBottom: boolean }>();
 
@@ -304,20 +304,6 @@ export function ConversationPage() {
   const fileInputRef = useRef<HTMLInputElement>(null);
   const composerRef = useRef<HTMLTextAreaElement>(null);
 
-  useEffect(() => {
-    setReplyTo(null);
-    setForwardTarget(null);
-    setSearchOpen(false);
-    setMediaDrawerOpen(false);
-    setPollDialogOpen(false);
-    setSearchQuery('');
-    setDisplayCount(150);
-    setFirstUnreadId(null);
-    setFirstUnreadJumpDismissed(false);
-    setNewMessagesWhileAway(0);
-    previousMessageIdsRef.current = new Set();
-    firstUnreadComputedRef.current = false;
-  }, [id]);
 
   useEffect(() => {
     if (firstUnreadComputedRef.current) return;