fix(web): prevent auto-scroll when toggling work log expansion

Expanding a work log group during a running session would trigger
scheduleStickToBottom via the timelineEntries effect, yanking the
viewport to the bottom. Disable auto-scroll on toggle so the user
stays where they clicked; the scroll-to-bottom button is shown if
they want to jump back.

Author: Marve10s

apps/web/src/components/ChatView.tsx

@@ -3434,12 +3434,18 @@ export default function ChatView({ threadId }: ChatViewProps) {
     }
     return false;
   };
-  const onToggleWorkGroup = useCallback((groupId: string) => {
-    setExpandedWorkGroups((existing) => ({
-      ...existing,
-      [groupId]: !existing[groupId],
-    }));
-  }, []);
+  const onToggleWorkGroup = useCallback(
+    (groupId: string) => {
+      cancelPendingStickToBottom();
+      shouldAutoScrollRef.current = false;
+      setShowScrollToBottom(true);
+      setExpandedWorkGroups((existing) => ({
+        ...existing,
+        [groupId]: !existing[groupId],
+      }));
+    },
+    [cancelPendingStickToBottom],
+  );
   const onExpandTimelineImage = useCallback((preview: ExpandedImagePreview) => {
     setExpandedImage(preview);
   }, []);