test(pi): align auth and extension checks with current runtime

tests/unit/pi-event-projector.test.ts

@@ -465,7 +465,7 @@ describe('Pi event projector', () => {
       terminalReason: 'failed',
       error: {
         code: 'CODING_PROVIDER_AUTH_REQUIRED',
-        message: '模型服务身份上下文无效，请重试；若仍失败请重新登录。',
+        message: '登录已失效，请重新登录后继续。',
         recoverable: true,
       },
     });
@@ -530,7 +530,7 @@ describe('Pi event projector', () => {
       terminalReason: 'failed',
       error: {
         code: 'CODING_PROVIDER_AUTH_REQUIRED',
-        message: '模型服务身份上下文无效，请重试；若仍失败请重新登录。',
+        message: '登录已失效，请重新登录后继续。',
         recoverable: true,
       },
     });