fix(opencode): switch session models without restart

tests/unit/project-agent-runtime.test.ts

@@ -231,6 +231,62 @@ describe('project Agent runtime readiness', () => {
     }
   });
 
+  it('keeps a deleted and recreated same-id Agent pending until generation rollover', async () => {
+    const projectPath = await mkdtemp(path.join(tmpdir(), 'makelore-agent-recreated-same-id-'));
+    try {
+      const initial = await createInitialProjectConfig(projectPath);
+      const agent = createAgent();
+      const original = await writeProjectConfig(projectPath, {
+        ...initial,
+        initialized: true,
+        agents: [agent],
+      });
+      let runtimeGeneration = 1;
+      const manager = {
+        getRuntimeGeneration: () => runtimeGeneration,
+        getRuntimeGenerationProvenance: () => 'fresh' as const,
+      };
+      const listAgents = vi.fn(async () => [{ id: agent.id }]);
+
+      await expect(preflightProjectAgentRuntime(
+        manager,
+        projectPath,
+        { listAgents },
+        agent.id,
+      )).resolves.toEqual({ ready: true, runtimeGeneration: 1 });
+
+      const removed = await writeProjectConfig(projectPath, {
+        ...original,
+        agents: [],
+      });
+      await observeProjectAgentRuntime(manager, projectPath, removed);
+      const recreated = await writeProjectConfig(projectPath, {
+        ...removed,
+        agents: [agent],
+      });
+      await observeProjectAgentRuntime(manager, projectPath, recreated);
+      listAgents.mockClear();
+
+      await expect(preflightProjectAgentRuntime(
+        manager,
+        projectPath,
+        { listAgents },
+        agent.id,
+      )).resolves.toEqual({ ready: false, runtimeGeneration: 1 });
+      expect(listAgents).not.toHaveBeenCalled();
+
+      runtimeGeneration = 2;
+      await expect(preflightProjectAgentRuntime(
+        manager,
+        projectPath,
+        { listAgents },
+        agent.id,
+      )).resolves.toEqual({ ready: true, runtimeGeneration: 2 });
+    } finally {
+      await rm(projectPath, { recursive: true, force: true });
+    }
+  });
+
   it('never treats an attached runtime generation as an authoritative Agent baseline', async () => {
     const projectPath = await mkdtemp(path.join(tmpdir(), 'makelore-agent-attached-runtime-'));
     try {