fix(persistence): clear canonical active workspace key on worktree owner removal (#6255)

Worktree session owners are removed by their raw id, but activeWorkspaceKey
stores the canonical worktree:<id> form, so deleting a worktree left the
persisted active key pointing at the removed workspace in every partition.
Match both forms in deleteOwnerKeyedSessionFields so every owner-removal
path (worktree delete, repo pruning, invalid-layout purge) clears it.

Co-authored-by: Neil <neil@stably.ai>

src/main/persistence/persistence-host-partitioned-sessions.test.ts

@@ -475,6 +475,7 @@ describe('Store host-partitioned workspace sessions', () => {
     const makeSession = (): ReturnType<typeof makeHostSession> => ({
       ...makeHostSession('repo-ssh'),
       activeWorktreeId: worktreeId,
+      activeWorkspaceKey: worktreeWorkspaceKey(worktreeId),
       lastVisitedAtByWorktreeId: { [worktreeId]: 123 },
       tabsByWorktree: {
         [worktreeId]: [makeTerminalTab({ id: 'stale-tab', worktreeId })]
@@ -493,6 +494,7 @@ describe('Store host-partitioned workspace sessions', () => {
       expect(store.getWorkspaceSession(hostId)).toMatchObject({
         tabsByWorktree: {},
         activeWorktreeId: null,
+        activeWorkspaceKey: null,
         lastVisitedAtByWorktreeId: {},
         terminalTopologyRevisionByRepoId: { 'repo-ssh': 1 }
       })

src/main/persistence/restoring-sessions/session-owner-fields.ts

@@ -5,6 +5,7 @@ import {
   getWorktreeIdFromHostIdentity,
   isWorktreeHostIdentity
 } from '../../../shared/worktree/host-qualified-identity'
+import { worktreeWorkspaceKey } from '../../../shared/workspace-scope'
 import { SESSION_FIELDS_PRUNED_BY_OWNER_KEY } from '../../orca-profiles/profile-project-session-field-disposition'
 
 // Repo-keyed topology revisions advance rather than delete; host-qualified recency keys need a scan.
@@ -91,7 +92,11 @@ export function deleteOwnerKeyedSessionFields(
       }
     }
   }
-  if (next.activeWorkspaceKey === ownerKey) {
+  // Worktree owners are raw ids, but the active key stores their canonical worktree: form.
+  if (
+    next.activeWorkspaceKey === ownerKey ||
+    next.activeWorkspaceKey === worktreeWorkspaceKey(ownerKey)
+  ) {
     next.activeWorkspaceKey = null
   }
   if (next.activeWorktreeId === ownerKey) {