fix: honor Harness default agent preset for IM sessions

test/channels/dingtalk/production.test.mjs

@@ -58,6 +58,7 @@ test('production assembly keeps secrets in credentials and creates per-bot runti
   assert.equal(seen.controllerOptions.credentials, credentials);
   assert.equal(seen.harnessOptions.baseUrl.href, 'http://127.0.0.1:3080/');
   assert.equal(seen.harnessOptions.autostart, false);
+  assert.equal(Object.hasOwn(seen.harnessOptions, 'agentPreset'), false);
   const runtime = await seen.controllerOptions.createRuntime({
     botId: 'dt_abc',
     config: { botId: 'dt_abc', clientId: 'dingabc' },
@@ -71,4 +72,21 @@ test('production assembly keeps secrets in credentials and creates per-bot runti
   assert.equal(seen.supervisorClosed, true);
   assert.equal(seen.controllerClosed, true);
   assert.equal(seen.harnessStopped, true);
+
+  const productionWithPreset = await createProductionController({
+    credentials,
+    webServer: { port: 3080 },
+    logger: () => console,
+  }, { dataDir: directory, agentPreset: 'router-standard' }, {
+    ConfigStore,
+    DeviceAuth,
+    StateStore,
+    HarnessClient: Harness,
+    Controller,
+    Runtime,
+    createConnectionSupervisor: () => supervisor,
+  });
+
+  assert.equal(seen.harnessOptions.agentPreset, 'router-standard');
+  await productionWithPreset.close();
 });

test/channels/weixin/harness-client.test.mjs

@@ -45,6 +45,34 @@ test('all legacy channel clients now use the shared Harness RPC transport', asyn
   }
 });
 
+test('HarnessClient lets the Host resolve an omitted agent preset and forwards an explicit override', async () => {
+  const createPayload = async (options = {}) => {
+    const client = new HarnessClient({
+      baseUrl: 'http://127.0.0.1:3080',
+      workspace: '/tmp/default-workspace',
+      ...options,
+    });
+    let payload;
+    client.ensureRunning = async () => true;
+    client.workspaceId = async () => 'workspace-one';
+    client.rpc = async (method, value) => {
+      assert.equal(method, 'session.create');
+      payload = value;
+      return { sessionId: 'session-one' };
+    };
+
+    assert.equal(await client.createSession(), 'session-one');
+    return payload;
+  };
+
+  assert.deepEqual(await createPayload(), { workspaceId: 'workspace-one' });
+  assert.deepEqual(await createPayload({ agentPreset: 'router-standard' }), {
+    workspaceId: 'workspace-one',
+    agentPreset: 'router-standard',
+  });
+  assert.deepEqual(await createPayload({ agentPreset: null }), { workspaceId: 'workspace-one' });
+});
+
 test('HarnessClient lists only absolute workspace paths', async () => {
   const client = new HarnessClient({
     baseUrl: 'http://127.0.0.1:3080',