fix(coding-runtime): close Pi extension lifecycle races

tests/unit/pi-conversation-runtime.test.ts

@@ -14,6 +14,7 @@ import {
 import { PiConversationRuntime } from '../../electron/coding-runtime/pi/runtime';
 import { PiSessionProjectionError } from '../../electron/coding-runtime/pi/session-projector';
 import { PiSessionRegistry } from '../../electron/coding-runtime/pi/session-registry';
+import { PiManagedExtensionHost } from '../../electron/coding-runtime/pi/extension-host';
 import {
   PiWorkerPool,
   type PiConversationWorker,
@@ -114,6 +115,18 @@ class RuntimeFakeWorker implements PiConversationWorker {
   }
 }
 
+class TrackingExtensionHost extends PiManagedExtensionHost {
+  readonly runs = new Map<string, { generation: number; runId: string }>();
+
+  override async bindRun(conversationId: string, generation: number, runId: string): Promise<void> {
+    this.runs.set(conversationId, { generation, runId });
+  }
+
+  override async clearRun(conversationId: string, _generation: number, runId?: string): Promise<void> {
+    if (!runId || this.runs.get(conversationId)?.runId === runId) this.runs.delete(conversationId);
+  }
+}
+
 afterEach(async () => {
   await Promise.all(roots.splice(0).map((root) => rm(root, { recursive: true, force: true })));
 });
@@ -189,10 +202,12 @@ describe('Pi Conversation runtime', () => {
         };
       },
     });
+    const trackingHost = new TrackingExtensionHost();
     const runtime = new PiConversationRuntime({
       pool,
       registry: new PiSessionRegistry({ projectStore }),
       createId: (kind) => `${kind}-fixed`,
+      extensionHost: trackingHost,
       resolveModel: async (candidate) => {
         if (candidate.accountId !== 'account-b' || candidate.modelId !== 'model-b') {
           throw new Error('model unavailable');
@@ -483,6 +498,17 @@ describe('Pi Conversation runtime', () => {
     await expect(runtime.getSnapshot(forkTarget.id)).rejects.toMatchObject({
       publicError: { code: 'CODING_CONVERSATION_NOT_FOUND' },
     });
+    await runtime.prompt({
+      clientRequestId: 'request-active-recover',
+      conversationId: left.id,
+      mode: 'prompt',
+      text: 'Recover this active run',
+      attachments: [],
+    });
+    expect(trackingHost.runs.get(left.id)?.runId).toBe('run-fixed');
+    await runtime.recover(left.id);
+    expect(trackingHost.runs.has(left.id)).toBe(false);
+    expect((await runtime.getSnapshot(left.id)).run).toEqual({ status: 'idle' });
     unsubscribe();
   });
 });