fix(sidebar): key parent-expansion per render context (#1302)

The same session can appear in two render contexts at once — most
visibly under "Recent" and under its project's root group. Expansion
state was keyed by bare session id, so toggling the chevron in one
context flipped it in the other; the user clicked one row and a
duplicate elsewhere expanded/collapsed in sync.

Switch the expansion set to composite keys of the form
`<renderContext>:<active|archived>:<sessionId>`. SessionNodeItem
already computes this exact shape for its menu instance key
(menuInstanceKey); reuse it as expansionKey so the two render-time
instances of one session keep independent expand state. Updated:

- isExpanded reads `expandedParents.has(expansionKey)`.
- Chevron click / Enter / Space pass `expansionKey` to toggleParent
  instead of session.id.
- The memo-equality check compares the same composite key on both
  sides so it correctly re-renders when only one context's state
  changes.
- toggleParent's parameter is renamed `expansionKey` to reflect the
  new shape; the implementation is unchanged.
- The auto-expand-parent-on-subagent-navigation effect doesn't know
  which context the user will look at the parent in, so it fans the
  parentID out to all four (project|recent) × (active|archived)
  combinations.

Storage is bumped to `oc.sessions.expandedParents.v2`. Existing v1
data (bare session ids) is one-shot migrated by fanning each id
across all four contexts and rewritten under the v2 key; the v1 key
is then removed so a downgrade-then-reupgrade doesn't re-migrate.

Co-authored-by: vhqtvn <8930337+vhqtvn@users.noreply.github.com>

packages/ui/src/components/session/SessionSidebar.tsx

@@ -81,7 +81,13 @@ const PROJECT_COLLAPSE_STORAGE_KEY = 'oc.sessions.projectCollapse';
 const GROUP_ORDER_STORAGE_KEY = 'oc.sessions.groupOrder';
 const GROUP_COLLAPSE_STORAGE_KEY = 'oc.sessions.groupCollapse';
 const PROJECT_ACTIVE_SESSION_STORAGE_KEY = 'oc.sessions.activeSessionByProject';
-const SESSION_EXPANDED_STORAGE_KEY = 'oc.sessions.expandedParents';
+// v2 key holds composite "${renderContext}:${active|archived}:${sessionId}"
+// entries so the same session in different render contexts (e.g. "Recent"
+// and a project's root) has independent expand state. v1 held bare session
+// ids; useSidebarPersistence migrates v1 data on first read by fanning each
+// id into all four context combinations.
+const SESSION_EXPANDED_STORAGE_KEY = 'oc.sessions.expandedParents.v2';
+const LEGACY_SESSION_EXPANDED_STORAGE_KEY = 'oc.sessions.expandedParents';
 const SESSION_PINNED_STORAGE_KEY = 'oc.sessions.pinned';
 
 type PrVisualState = 'draft' | 'open' | 'blocked' | 'merged' | 'closed';
@@ -521,6 +527,7 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     safeStorage,
     keys: {
       sessionExpanded: SESSION_EXPANDED_STORAGE_KEY,
+      sessionExpandedLegacy: LEGACY_SESSION_EXPANDED_STORAGE_KEY,
       projectCollapse: PROJECT_COLLAPSE_STORAGE_KEY,
       sessionPinned: SESSION_PINNED_STORAGE_KEY,
       groupOrder: GROUP_ORDER_STORAGE_KEY,
@@ -677,16 +684,25 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     sessionEvents.requestDirectoryDialog();
   }, []);
 
-  // Auto-expand parent session when navigating to a subagent (child) session
+  // Auto-expand parent session when navigating to a subagent (child) session.
+  // We don't know which render context the user will look at the parent in
+  // (Recent, project root, archived bucket, ...), so fan out across all
+  // four combinations to ensure it's expanded wherever it appears.
   React.useEffect(() => {
     if (!currentSessionId) return;
     const current = sessions.find((s) => s.id === currentSessionId);
     const parentID = (current as Session & { parentID?: string | null })?.parentID;
     if (!parentID) return;
+    const keysToAdd = [
+      `project:active:${parentID}`,
+      `project:archived:${parentID}`,
+      `recent:active:${parentID}`,
+      `recent:archived:${parentID}`,
+    ];
     setExpandedParents((prev) => {
-      if (prev.has(parentID)) return prev;
+      if (keysToAdd.every((k) => prev.has(k))) return prev;
       const next = new Set(prev);
-      next.add(parentID);
+      keysToAdd.forEach((k) => next.add(k));
       try {
         safeStorage.setItem(SESSION_EXPANDED_STORAGE_KEY, JSON.stringify(Array.from(next)));
       } catch { /* ignored */ }
@@ -694,13 +710,13 @@ export const SessionSidebar: React.FC<SessionSidebarProps> = ({
     });
   }, [currentSessionId, sessions, safeStorage]);
 
-  const toggleParent = React.useCallback((sessionId: string) => {
+  const toggleParent = React.useCallback((expansionKey: string) => {
     setExpandedParents((prev) => {
       const next = new Set(prev);
-      if (next.has(sessionId)) {
-        next.delete(sessionId);
+      if (next.has(expansionKey)) {
+        next.delete(expansionKey);
       } else {
-        next.add(sessionId);
+        next.add(expansionKey);
       }
       try {
         safeStorage.setItem(SESSION_EXPANDED_STORAGE_KEY, JSON.stringify(Array.from(next)));