feat: enhance LocalAgent configuration and UI components

- Updated .env.example to provide clearer configuration instructions and API key setup.
- Removed debug_env.py as it was no longer needed.
- Refactored main.py to streamline application initialization and workspace setup.
- Introduced a new HistoryManager for managing task execution history.
- Enhanced UI components in chat_view.py and task_guide_view.py to improve user interaction and code preview functionality.
- Added loading indicators and improved task history display in the UI.
- Implemented unit tests for history management and intent classification.

history/__init__.py

@@ -0,0 +1,2 @@
+# 历史记录模块
+

history/manager.py

@@ -0,0 +1,189 @@
+"""
+任务历史记录管理器
+保存和加载任务执行历史
+"""
+
+import json
+from datetime import datetime
+from pathlib import Path
+from typing import Optional, List
+from dataclasses import dataclass, asdict
+
+
+@dataclass
+class TaskRecord:
+    """任务记录"""
+    task_id: str
+    timestamp: str
+    user_input: str
+    intent_label: str
+    intent_confidence: float
+    execution_plan: str
+    code: str
+    success: bool
+    duration_ms: int
+    stdout: str
+    stderr: str
+    log_path: str
+
+
+class HistoryManager:
+    """
+    历史记录管理器
+    
+    将任务历史保存为 JSON 文件
+    """
+    
+    MAX_HISTORY_SIZE = 100  # 最多保存 100 条记录
+    
+    def __init__(self, workspace_path: Optional[Path] = None):
+        if workspace_path:
+            self.workspace = workspace_path
+        else:
+            self.workspace = Path(__file__).parent.parent / "workspace"
+        
+        self.history_file = self.workspace / "history.json"
+        self._history: List[TaskRecord] = []
+        self._load()
+    
+    def _load(self):
+        """从文件加载历史记录"""
+        if self.history_file.exists():
+            try:
+                with open(self.history_file, 'r', encoding='utf-8') as f:
+                    data = json.load(f)
+                    self._history = [TaskRecord(**record) for record in data]
+            except (json.JSONDecodeError, TypeError, KeyError) as e:
+                print(f"[警告] 加载历史记录失败: {e}")
+                self._history = []
+        else:
+            self._history = []
+    
+    def _save(self):
+        """保存历史记录到文件"""
+        try:
+            # 确保目录存在
+            self.history_file.parent.mkdir(parents=True, exist_ok=True)
+            
+            with open(self.history_file, 'w', encoding='utf-8') as f:
+                data = [asdict(record) for record in self._history]
+                json.dump(data, f, ensure_ascii=False, indent=2)
+        except Exception as e:
+            print(f"[警告] 保存历史记录失败: {e}")
+    
+    def add_record(
+        self,
+        task_id: str,
+        user_input: str,
+        intent_label: str,
+        intent_confidence: float,
+        execution_plan: str,
+        code: str,
+        success: bool,
+        duration_ms: int,
+        stdout: str = "",
+        stderr: str = "",
+        log_path: str = ""
+    ) -> TaskRecord:
+        """
+        添加一条任务记录
+        
+        Args:
+            task_id: 任务 ID
+            user_input: 用户输入
+            intent_label: 意图标签
+            intent_confidence: 意图置信度
+            execution_plan: 执行计划
+            code: 生成的代码
+            success: 是否执行成功
+            duration_ms: 执行耗时（毫秒）
+            stdout: 标准输出
+            stderr: 标准错误
+            log_path: 日志文件路径
+            
+        Returns:
+            TaskRecord: 创建的记录
+        """
+        record = TaskRecord(
+            task_id=task_id,
+            timestamp=datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
+            user_input=user_input,
+            intent_label=intent_label,
+            intent_confidence=intent_confidence,
+            execution_plan=execution_plan,
+            code=code,
+            success=success,
+            duration_ms=duration_ms,
+            stdout=stdout,
+            stderr=stderr,
+            log_path=log_path
+        )
+        
+        # 添加到列表开头（最新的在前）
+        self._history.insert(0, record)
+        
+        # 限制历史记录数量
+        if len(self._history) > self.MAX_HISTORY_SIZE:
+            self._history = self._history[:self.MAX_HISTORY_SIZE]
+        
+        # 保存
+        self._save()
+        
+        return record
+    
+    def get_all(self) -> List[TaskRecord]:
+        """获取所有历史记录"""
+        return self._history.copy()
+    
+    def get_recent(self, count: int = 10) -> List[TaskRecord]:
+        """获取最近的 N 条记录"""
+        return self._history[:count]
+    
+    def get_by_id(self, task_id: str) -> Optional[TaskRecord]:
+        """根据任务 ID 获取记录"""
+        for record in self._history:
+            if record.task_id == task_id:
+                return record
+        return None
+    
+    def clear(self):
+        """清空历史记录"""
+        self._history = []
+        self._save()
+    
+    def get_stats(self) -> dict:
+        """获取统计信息"""
+        if not self._history:
+            return {
+                'total': 0,
+                'success': 0,
+                'failed': 0,
+                'success_rate': 0.0,
+                'avg_duration_ms': 0
+            }
+        
+        total = len(self._history)
+        success = sum(1 for r in self._history if r.success)
+        failed = total - success
+        avg_duration = sum(r.duration_ms for r in self._history) / total
+        
+        return {
+            'total': total,
+            'success': success,
+            'failed': failed,
+            'success_rate': success / total if total > 0 else 0.0,
+            'avg_duration_ms': int(avg_duration)
+        }
+
+
+# 全局单例
+_manager: Optional[HistoryManager] = None
+
+
+def get_history_manager(workspace_path: Optional[Path] = None) -> HistoryManager:
+    """获取历史记录管理器单例"""
+    global _manager
+    if _manager is None:
+        _manager = HistoryManager(workspace_path)
+    return _manager
+