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.

tests/test_intent_classifier.py

@@ -0,0 +1,94 @@
+"""
+意图分类器单元测试
+"""
+
+import unittest
+import sys
+from pathlib import Path
+
+# 添加项目根目录到路径
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from intent.labels import CHAT, EXECUTION, VALID_LABELS, EXECUTION_CONFIDENCE_THRESHOLD
+
+
+class TestIntentLabels(unittest.TestCase):
+    """意图标签测试"""
+    
+    def test_labels_defined(self):
+        """测试标签已定义"""
+        self.assertEqual(CHAT, "chat")
+        self.assertEqual(EXECUTION, "execution")
+    
+    def test_valid_labels(self):
+        """测试有效标签集合"""
+        self.assertIn(CHAT, VALID_LABELS)
+        self.assertIn(EXECUTION, VALID_LABELS)
+        self.assertEqual(len(VALID_LABELS), 2)
+    
+    def test_confidence_threshold(self):
+        """测试置信度阈值"""
+        self.assertGreater(EXECUTION_CONFIDENCE_THRESHOLD, 0)
+        self.assertLessEqual(EXECUTION_CONFIDENCE_THRESHOLD, 1)
+
+
+class TestIntentClassifierParsing(unittest.TestCase):
+    """意图分类器解析测试（不需要 API）"""
+    
+    def setUp(self):
+        from intent.classifier import IntentClassifier
+        self.classifier = IntentClassifier()
+    
+    def test_parse_valid_chat_response(self):
+        """测试解析有效的 chat 响应"""
+        response = '{"label": "chat", "confidence": 0.95, "reason": "这是一个问答"}'
+        result = self.classifier._parse_response(response)
+        self.assertEqual(result.label, CHAT)
+        self.assertEqual(result.confidence, 0.95)
+        self.assertEqual(result.reason, "这是一个问答")
+    
+    def test_parse_valid_execution_response(self):
+        """测试解析有效的 execution 响应"""
+        response = '{"label": "execution", "confidence": 0.9, "reason": "需要复制文件"}'
+        result = self.classifier._parse_response(response)
+        self.assertEqual(result.label, EXECUTION)
+        self.assertEqual(result.confidence, 0.9)
+    
+    def test_parse_low_confidence_execution(self):
+        """测试低置信度的 execution 降级为 chat"""
+        response = '{"label": "execution", "confidence": 0.5, "reason": "不太确定"}'
+        result = self.classifier._parse_response(response)
+        # 低于阈值应该降级为 chat
+        self.assertEqual(result.label, CHAT)
+    
+    def test_parse_invalid_label(self):
+        """测试无效标签降级为 chat"""
+        response = '{"label": "unknown", "confidence": 0.9, "reason": "测试"}'
+        result = self.classifier._parse_response(response)
+        self.assertEqual(result.label, CHAT)
+    
+    def test_parse_invalid_json(self):
+        """测试无效 JSON 降级为 chat"""
+        response = 'not a json'
+        result = self.classifier._parse_response(response)
+        self.assertEqual(result.label, CHAT)
+        self.assertEqual(result.confidence, 0.0)
+    
+    def test_extract_json_with_prefix(self):
+        """测试从带前缀的文本中提取 JSON"""
+        text = 'Here is the result: {"label": "chat", "confidence": 0.8, "reason": "test"}'
+        json_str = self.classifier._extract_json(text)
+        self.assertTrue(json_str.startswith('{'))
+        self.assertTrue(json_str.endswith('}'))
+    
+    def test_extract_json_with_suffix(self):
+        """测试从带后缀的文本中提取 JSON"""
+        text = '{"label": "chat", "confidence": 0.8, "reason": "test"} That is my answer.'
+        json_str = self.classifier._extract_json(text)
+        self.assertTrue(json_str.startswith('{'))
+        self.assertTrue(json_str.endswith('}'))
+
+
+if __name__ == '__main__':
+    unittest.main()
+