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/sidebar/SessionNodeItem.tsx

@@ -59,7 +59,7 @@ type Props = {
   setEditTitle: (value: string) => void;
   handleSaveEdit: () => void;
   handleCancelEdit: () => void;
-  toggleParent: (sessionId: string) => void;
+  toggleParent: (expansionKey: string) => void;
   handleSessionSelect: (sessionId: string, sessionDirectory: string | null, isMissingDirectory: boolean, projectId?: string | null) => void;
   handleSessionDoubleClick: () => void;
   togglePinnedSession: (sessionId: string) => void;
@@ -157,7 +157,18 @@ const areEqual = (prev: Props, next: Props): boolean => {
     }
   }
   if (prev.pinnedSessionIds.has(prevSessionId) !== next.pinnedSessionIds.has(nextSessionId)) return false;
-  if (prev.expandedParents.has(prevSessionId) !== next.expandedParents.has(nextSessionId)) return false;
+  // Expansion is keyed per render context, so compare the composite key
+  // matching the one isExpanded reads from in render. If a session appears
+  // in two contexts (project + recent), they have independent state.
+  {
+    const prevRenderContext = prev.renderContext ?? 'project';
+    const nextRenderContext = next.renderContext ?? 'project';
+    const prevArchived = prev.archivedBucket ?? false;
+    const nextArchived = next.archivedBucket ?? false;
+    const prevExpansionKey = `${prevRenderContext}:${prevArchived ? 'archived' : 'active'}:${prevSessionId}`;
+    const nextExpansionKey = `${nextRenderContext}:${nextArchived ? 'archived' : 'active'}:${nextSessionId}`;
+    if (prev.expandedParents.has(prevExpansionKey) !== next.expandedParents.has(nextExpansionKey)) return false;
+  }
   if (prev.hasSessionSearchQuery !== next.hasSessionSearchQuery) return false;
   if (prev.normalizedSessionSearchQuery !== next.normalizedSessionSearchQuery) return false;
   if (prev.notifyOnSubtasks !== next.notifyOnSubtasks) return false;
@@ -312,7 +323,11 @@ function SessionNodeItemComponent(props: Props): React.ReactNode {
   const sessionTitle = resolvedSession.title || t('sessions.sidebar.session.untitled');
   const hasChildren = node.children.length > 0;
   const isPinnedSession = pinnedSessionIds.has(session.id);
-  const isExpanded = hasSessionSearchQuery ? true : expandedParents.has(session.id);
+  // Per-render-context expansion key: the same session can appear in both
+  // the project's root and the "Recent" list, and expanding one should not
+  // expand the other. Matches the format of menuInstanceKey.
+  const expansionKey = menuInstanceKey;
+  const isExpanded = hasSessionSearchQuery ? true : expandedParents.has(expansionKey);
   const isSubtaskSession = Boolean((resolvedSession as Session & { parentID?: string | null }).parentID);
   const unseenCount = useSessionUnseenCount(session.id);
   const needsAttention = unseenCount > 0 && (!isSubtaskSession || notifyOnSubtasks);
@@ -529,13 +544,13 @@ function SessionNodeItemComponent(props: Props): React.ReactNode {
       tabIndex={0}
       onClick={(event) => {
         event.stopPropagation();
-        toggleParent(session.id);
+        toggleParent(expansionKey);
       }}
       onKeyDown={(event) => {
         if (event.key === 'Enter' || event.key === ' ') {
           event.preventDefault();
           event.stopPropagation();
-          toggleParent(session.id);
+          toggleParent(expansionKey);
         }
       }}
       className={cn(