fix: prevent duplicate AI design stream reconnects

.project-docs/30-worklog/tasks/20260819-makelore-session-freeze-7c4e.md

@@ -0,0 +1,86 @@
+# Task: Fix AI design rapid session switching freeze
+
+## Identity
+
+- Task ID: 20260819-makelore-session-freeze-7c4e
+- Mode: Feature
+- Branch: codex/20260818-prompt-museum-client-4f7a-prompt-museum-client
+- Worktree: D:\mk-4f7a
+- Base commit: f8d82e6c19536bbd9bd7d70a72efbf7ec163aeb4
+- Owner: codex
+- Status: Ready for integration
+
+## Scope
+
+- Diagnose and fix the Makelore AI Design client freeze reported when a user
+  rapidly switches Conversations after login.
+- Keep the change limited to the Renderer task-stream lifecycle and its unit
+  regression coverage; do not change the Works API or persistent Agent Session
+  contract.
+
+## Intent And Constraints
+
+- Preserve the existing Workspace + Conversation identity and generation
+  guards, including stale-stream isolation and REST reconciliation after the
+  Canvas effect is cleaned up.
+- Do not issue a second event-stream open for the same active Workspace +
+  Conversation solely because reconciliation was requested while its stream
+  is `connecting`. An explicit Conversation selection may invalidate the old
+  identity and start the newly selected Conversation's stream. Only a known
+  `degraded` stream may be forced closed and reopened by reconciliation.
+- Use a regression test that models an unresolved `openImageWorkspaceTaskEvents`
+  Promise, because the underlying connection attempt is not cancellable once
+  started.
+
+## Outcome
+
+- Confirmed the freeze mechanism: Canvas effect cleanup marks task-stream
+  reconciliation while the stream is still `connecting`; the next connect
+  call treated every non-`connected` state as broken, closed the logical
+  stream, and started another request. The old Promise could not be cancelled
+  and only closed its EventSource after eventually resolving, so rapid
+  switching accumulated concurrent connection attempts.
+- Changed `connectTaskStream` to force a close/reconnect only for `degraded`
+  streams. An in-flight `connecting` stream is reused while Conversation and
+  task REST reconciliation still runs.
+- Added a store regression test proving reconciliation does not issue a second
+  stream-open request while the first one is unresolved.
+- Audited the adjacent Main SSE relay close timing; the existing `finally`
+  path closes a subscription after a response is already closed, and no
+  reliable red test proved an additional leak in this task, so no Main/API
+  change was made.
+
+## Verification
+
+- New regression before the fix: failed as expected (`openImageWorkspaceTaskEvents`
+  was called twice instead of once).
+- `node_modules\\.bin\\vitest.cmd run tests/unit/image-workspace-store.test.ts
+  --reporter=dot` — passed, 1 file / 31 tests.
+- `node_modules\\.bin\\vitest.cmd run tests/unit/image-canvas-page.test.tsx
+  tests/unit/works-square-design-workspace.test.ts --reporter=dot` — passed,
+  2 files / 78 tests. Existing React `act(...)` warnings were emitted by an
+  unrelated auth test.
+- `node_modules\\.bin\\eslint.cmd src/stores/image-workspace.ts
+  tests/unit/image-workspace-store.test.ts` — passed.
+- `node_modules\\.bin\\tsc.cmd --noEmit` — passed.
+- `git diff --check` — passed.
+- `check_doc_drift.py --task-id 20260819-makelore-session-freeze-7c4e` — passed.
+- Independent Sol read-only final review — PASS. The review noted the
+  untested extreme A→B→A case where a deliberately stalled old open request
+  may later be replaced; that is retained as a separate follow-up rather than
+  part of the same-identity reconciliation race.
+
+## Follow-ups
+
+- Run a real logged-in Electron smoke test that alternates two or more
+  Conversations while the event-stream handshake is deliberately slow; local
+  unit tests prove the duplicate-open race but do not validate a deployed Works
+  gateway or production network behavior.
+- If production telemetry later shows a WebSocket handshake that never
+  resolves, track a separate cancellation/timeout task instead of coupling it
+  to this Renderer race fix.
+
+## Promotion Candidates
+
+- None. The fix restores the existing client stream-lifecycle invariant and
+  does not introduce a new architectural decision or canonical contract.

src/stores/image-workspace.ts

@@ -1026,7 +1026,7 @@ export const useImageWorkspaceStore = create<ImageWorkspaceState>((set, get) =>
       const conversationId = get().activeConversationId;
       const shouldReconcile = reconcileTaskStateOnNextConnect;
       reconcileTaskStateOnNextConnect = false;
-      if (shouldReconcile && get().taskStreamState !== 'connected') {
+      if (shouldReconcile && get().taskStreamState === 'degraded') {
         closeTaskEventSource();
       }
       if (workspaceId && conversationId) startTaskStream(workspaceId, conversationId);

tests/unit/image-workspace-store.test.ts

@@ -385,6 +385,20 @@ describe('AI design task event store', () => {
       .toEqual(['继续优化海报', '已完成最新方向整理。']);
   });
 
+  it('keeps the in-flight stream connection when reconciliation is requested', async () => {
+    const pendingSource = deferred<EventSource>();
+    openImageWorkspaceTaskEventsMock.mockReturnValue(pendingSource.promise);
+
+    await useImageWorkspaceStore.getState().load();
+    expect(useImageWorkspaceStore.getState().taskStreamState).toBe('connecting');
+    expect(openImageWorkspaceTaskEventsMock).toHaveBeenCalledOnce();
+
+    useImageWorkspaceStore.getState().markTaskStreamNeedsReconciliation();
+    useImageWorkspaceStore.getState().connectTaskStream();
+
+    expect(openImageWorkspaceTaskEventsMock).toHaveBeenCalledOnce();
+  });
+
   it('recovers a committed generation task when the Agent Run fails afterward', async () => {
     const source = new MockEventSource();
     openImageWorkspaceTaskEventsMock.mockResolvedValue(source as unknown as EventSource);