fix(server): use in-process pino-pretty stream to avoid worker transport startup failure

- switch createServerLogger from pino transport target to in-process pretty stream\n- update changeset to cover @moonshot-ai/server\n- add test asserting pretty logger does not use ThreadStream\n- rename cli server test description

.changeset/fix-pino-pretty-runtime.md

@@ -1,5 +1,6 @@
 ---
 "@moonshot-ai/kimi-code": patch
+"@moonshot-ai/server": patch
 ---
 
 Fix server startup from npm-installed CLI packages when pretty logging is enabled.

apps/kimi-code/test/cli/server/server.test.ts

@@ -23,7 +23,7 @@ function makeProgram(): Command {
 }
 
 describe('kimi server', () => {
-  it('declares the pino pretty transport as a CLI runtime dependency', () => {
+  it('declares pino-pretty as a CLI runtime dependency', () => {
     const packageJson = JSON.parse(
       readFileSync(new URL('../../../package.json', import.meta.url), 'utf-8'),
     ) as { dependencies?: Record<string, string> };

packages/server/src/services/pinoLoggerService.ts

@@ -1,6 +1,7 @@
 import { Disposable } from '@moonshot-ai/agent-core';
 import { ILogService } from '@moonshot-ai/services';
 import { pino, type Logger, type LoggerOptions } from 'pino';
+import prettyStream from 'pino-pretty';
 
 export type ServerLogger = Logger;
 
@@ -19,18 +20,16 @@ export function createServerLogger(opts: CreateLoggerOptions): ServerLogger {
     timestamp: pino.stdTimeFunctions.isoTime,
   };
   if (pretty) {
-    return pino({
-      ...base,
-      transport: {
-        target: 'pino-pretty',
-        options: {
-          colorize: true,
-          translateTime: 'SYS:HH:MM:ss.l o',
-          ignore: 'pid,hostname',
-          singleLine: false,
-        },
-      },
-    });
+    return pino(
+      base,
+      prettyStream({
+        colorize: true,
+        translateTime: 'SYS:HH:MM:ss.l o',
+        ignore: 'pid,hostname',
+        singleLine: false,
+        destination: process.stdout,
+      }),
+    );
   }
   return pino(base);
 }

packages/server/test/start.test.ts

@@ -38,6 +38,7 @@ import {
   ISessionClientsService,
   IWSBroadcastService,
   IWSGateway,
+  createServerLogger,
   startServer,
   type LockContents,
   type RunningServer,
@@ -112,6 +113,19 @@ describe('startServer — lock + healthz smoke', () => {
   });
 });
 
+describe('createServerLogger', () => {
+  it('uses an in-process pretty stream instead of pino worker transport', () => {
+    const logger = createServerLogger({ level: 'info', pretty: true });
+    const streamSym = (pino as unknown as { symbols: { streamSym: symbol } }).symbols.streamSym;
+    const stream = logger[streamSym as keyof typeof logger] as unknown as NodeJS.WritableStream & {
+      constructor?: { name?: string };
+    };
+
+    expect(stream.constructor?.name).not.toBe('ThreadStream');
+    stream.end();
+  });
+});
+
 describe('startServer — web assets', () => {
   it('serves web assets from the server root without shadowing API routes', async () => {
     const assetsDir = join(tmpDir, 'web-assets');