fix(dingtalk): add observability logging to routing success paths

- Log when routing starts (instance found, bridge URL)
- Log bridge OK with reply length
- Log bridge error response
- Log instance not-running status
- Log batchSend OK with chunk count

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/services/agent-service/src/infrastructure/dingtalk/dingtalk-router.service.ts

@@ -604,6 +604,7 @@ export class DingTalkRouterService implements OnModuleInit, OnModuleDestroy {
     }
 
     if (instance.status !== 'running') {
+      this.logger.warn(`Instance ${instance.id} (${instance.name}) not running: status=${instance.status}`);
       this.reply(msg, `小龙虾「${instance.name}」当前状态为 ${instance.status}，暂时无法接收指令。`);
       return;
     }
@@ -615,6 +616,7 @@ export class DingTalkRouterService implements OnModuleInit, OnModuleDestroy {
     }
 
     const bridgeUrl = `http://${instance.serverHost}:${instance.hostPort}/task`;
+    this.logger.log(`Routing msgId=${msg.msgId} → instance ${instance.id} (${instance.name}) @ ${bridgeUrl}`);
 
     // sessionWebhook TTL is ~90 minutes (per DingTalk docs), but delivering the actual LLM
     // response synchronously makes the user wait with no feedback. Strategy:
@@ -641,8 +643,10 @@ export class DingTalkRouterService implements OnModuleInit, OnModuleDestroy {
         reply = typeof result.result === 'string'
           ? result.result
           : JSON.stringify(result.result, null, 2);
+        this.logger.log(`Bridge OK for instance ${instance.id}, reply length=${reply.length}`);
       } else {
         reply = result.error ?? '智能体没有返回内容。';
+        this.logger.warn(`Bridge returned error for instance ${instance.id}: ${reply}`);
       }
     } catch (e: any) {
       this.logger.error(`Bridge call failed for instance ${instance.id}:`, e.message);
@@ -680,6 +684,7 @@ export class DingTalkRouterService implements OnModuleInit, OnModuleDestroy {
             { 'x-acs-dingtalk-access-token': token },
           );
         }
+        this.logger.log(`batchSend OK for staffId=${staffId} msgId=${msgId} chunks=${chunks.length}`);
       })
       .catch((e: Error) =>
         this.logger.error(`batchSend failed for msgId=${msgId}:`, e.message),