修改自助建站-ai会话：删除会话的接口；

app/JsonRpc/PublicRpcService.php

@@ -4282,10 +4282,13 @@ class PublicRpcService implements PublicRpcServiceInterface
         // 删除会话
         Db::beginTransaction();
         try{
-            $result['ai_chat_session'] = AichatSession::where($where)->delete();
-            if(empty($result['ai_chat_session'])){
-                Db::rollBack();
-                return Result::error('删除会话消息失败！');
+            $aichat_session = AichatSession::where($where)->get()->all();
+            if(!empty($aichat_session)){
+                $result['ai_chat_session'] = AichatSession::where($where)->delete();
+                if(empty($result['ai_chat_session'])){
+                    Db::rollBack();
+                    return Result::error('删除会话消息失败！');
+                }
             }
             // 删除会话消息
             $aichat = Aichat::where($where)->get()->all();