revert: 撤回错误的修改，恢复原版本

用户指出SiliconFlow平台确实支持标准tool消息类型，之前的修改是错误的

版本: v3.0.7

main_v2.py

@@ -33,7 +33,7 @@ logging.basicConfig(level=logging.INFO)
 logger = logging.getLogger(__name__)
 
 # 创建应用
-app = FastAPI(title="AI对话系统 v3.0", version="3.0.1")
+app = FastAPI(title="AI对话系统 v2.0", version="2.0.0")
 
 # 静态文件和模板
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))

services/llm_service.py

@@ -536,15 +536,6 @@ class LLMService:
         # 消息历史已经包含了assistant的tool_calls和tool结果，直接使用
         final_messages = messages.copy()
         
-        # 添加提示：告诉模型直接根据工具结果回答，不要再调用工具
-        # 添加一个系统级别的提示
-        tool_hint = {
-            "role": "system",
-            "content": "请根据工具返回的结果直接回答用户的问题，不要再调用任何工具或搜索。如果结果不足以回答问题，请根据现有信息给出最好的回答，并说明信息的局限性。"
-        }
-        # 在工具结果之后添加提示
-        final_messages.append(tool_hint)
-        
         # 调用LLM生成最终回复
         url = f"{api_base.rstrip('/')}/chat/completions"
         headers = {
@@ -559,16 +550,6 @@ class LLMService:
         }
         
         logger.info(f"工具结果返回LLM: url={url}, model={model}, 消息数={len(final_messages)}")
-        # 打印消息内容（调试）
-        for i, msg in enumerate(final_messages):
-            role = msg.get('role')
-            content_preview = str(msg.get('content', ''))[:100] if msg.get('content') else 'None'
-            if role == 'tool':
-                logger.info(f"消息[{i}] role={role}, tool_call_id={msg.get('tool_call_id')}, content长度={len(msg.get('content',''))}")
-            elif role == 'assistant' and msg.get('tool_calls'):
-                logger.info(f"消息[{i}] role={role}, tool_calls={len(msg['tool_calls'])}")
-            else:
-                logger.info(f"消息[{i}] role={role}, content={content_preview}...")
         
         try:
             async with httpx.AsyncClient(timeout=60.0) as client:
@@ -581,27 +562,6 @@ class LLMService:
                 data = response.json()
                 content = data['choices'][0]['message']['content']
                 
-                # 过滤掉伪工具调用格式（某些模型如Kimi会输出这种内部格式）
-                # 模式：<|tool_calls_section_begin|>...<|tool_calls_section_end|>
-                import re
-                tool_pattern = r'<\|tool_calls_section_begin\|>.*?<\|tool_calls_section_end\|>'
-                content = re.sub(tool_pattern, '', content, flags=re.DOTALL)
-                
-                # 也过滤单个 tool_call 格式
-                tool_call_pattern = r'<\|tool_call_begin\|>.*?<\|tool_call_end\|>'
-                content = re.sub(tool_call_pattern, '', content, flags=re.DOTALL)
-                
-                # 清理可能残留的格式标记
-                content = content.replace('<|tool_calls_section_begin|>', '')
-                content = content.replace('<|tool_calls_section_end|>', '')
-                content = content.replace('<|tool_call_begin|>', '')
-                content = content.replace('<|tool_call_end|>', '')
-                content = content.replace('<|tool_call_argument_begin|>', '')
-                content = content.replace('<|tool_call_argument_end|>', '')
-                
-                # 清理多余空行
-                content = re.sub(r'\n{3,}', '\n\n', content).strip()
-                
                 return content, None
                 
         except Exception as e: