refactor(session): 清理代码 & RunnableConfig 传 sessionId

- AgentLoggingHook 改为从 config.metadata 读取 sessionId（线程安全）
- 移除 AgentLoggingHook 调试用的 metadata 日志
- TokenTrackingChatModel 日志降为 debug
- SessionContextHolder 移除未使用的 setAgentName/getAgentName
- ChatService 清理无用 import
- 修复 stream 路径下 ThreadLocal NPE

src/main/java/com/superbiz/agent/service/ChatService.java

@@ -1,6 +1,7 @@
 package com.superbiz.agent.service;
 
 import com.alibaba.cloud.ai.graph.OverAllState;
+import com.alibaba.cloud.ai.graph.RunnableConfig;
 import com.alibaba.cloud.ai.graph.agent.ReactAgent;
 import com.alibaba.cloud.ai.graph.agent.flow.agent.SupervisorAgent;
 import com.alibaba.cloud.ai.graph.exception.GraphRunnerException;
@@ -254,7 +255,12 @@ public class ChatService {
         SessionContextHolder.setSessionId(sessionId);
 
         try {
-            var response = agent.call(question);
+            // 通过 RunnableConfig 将 sessionId 传入 Hook（线程安全，异步也兼容）
+            var config = RunnableConfig.builder()
+                    .addMetadata("sessionId", sessionId)
+                    .build();
+
+            var response = agent.call(question, config);
             long duration = System.currentTimeMillis() - startTime;
 
             String answer = response.getText();