feat: 添加测试覆盖率并修复相关问题

refactor(redis_manager): 移除冗余的ConnectionError处理
refactor(event_handler): 优化Bot类型注解
refactor(factory): 移除未使用的GroupCardNoticeEvent

test: 添加全面的单元测试覆盖
- 添加test_import.py测试模块导入
- 添加test_debug.py测试插件加载调试
- 添加test_plugin_error.py测试错误处理
- 添加test_config_loader.py测试配置加载
- 添加test_redis_manager.py测试Redis管理
- 添加test_bot.py测试Bot功能
- 扩展test_models.py测试消息模型
- 添加test_plugin_manager_coverage.py测试插件管理
- 添加test_executor.py测试代码执行器
- 添加test_ws.py测试WebSocket
- 添加test_api.py测试API接口
- 添加test_core_managers.py测试核心管理模块

fix(plugin_manager): 修复插件加载日志变量问题

覆盖率已到达86%（忽略插件）

tests/test_executor.py

@@ -0,0 +1,187 @@
+import asyncio
+import pytest
+from unittest.mock import MagicMock, patch, AsyncMock
+import docker
+from core.utils.executor import CodeExecutor, initialize_executor
+
+# Mock 配置对象
+@pytest.fixture
+def mock_config():
+    config = MagicMock()
+    config.docker.base_url = None
+    config.docker.sandbox_image = "sandbox:latest"
+    config.docker.timeout = 5
+    config.docker.concurrency_limit = 2
+    config.docker.tls_verify = False
+    return config
+
+@pytest.fixture
+def mock_docker_client():
+    with patch("docker.from_env") as mock_from_env:
+        client = MagicMock()
+        mock_from_env.return_value = client
+        yield client
+
+@pytest.fixture
+def executor(mock_config, mock_docker_client):
+    return CodeExecutor(mock_config)
+
+def test_init_success(mock_config, mock_docker_client):
+    """测试初始化成功"""
+    executor = CodeExecutor(mock_config)
+    assert executor.docker_client is not None
+    mock_docker_client.ping.assert_called_once()
+
+def test_init_docker_error(mock_config):
+    """测试初始化 Docker 失败"""
+    with patch("docker.from_env", side_effect=docker.errors.DockerException("Docker error")):
+        executor = CodeExecutor(mock_config)
+        assert executor.docker_client is None
+
+def test_init_remote_docker(mock_config):
+    """测试初始化远程 Docker"""
+    mock_config.docker.base_url = "tcp://1.2.3.4:2375"
+    with patch("docker.DockerClient") as mock_client_cls:
+        executor = CodeExecutor(mock_config)
+        mock_client_cls.assert_called_once()
+        assert executor.docker_client is not None
+
+@pytest.mark.asyncio
+async def test_add_task_success(executor):
+    """测试添加任务成功"""
+    callback = AsyncMock()
+    await executor.add_task("print('hello')", callback)
+    assert executor.task_queue.qsize() == 1
+
+@pytest.mark.asyncio
+async def test_add_task_no_docker(mock_config):
+    """测试 Docker 未初始化时添加任务"""
+    with patch("docker.from_env", side_effect=docker.errors.DockerException):
+        executor = CodeExecutor(mock_config)
+        callback = AsyncMock()
+        with pytest.raises(RuntimeError, match="Docker环境未就绪"):
+            await executor.add_task("print('hello')", callback)
+
+@pytest.mark.asyncio
+async def test_worker_success(executor):
+    """测试 Worker 成功处理任务"""
+    # Mock _run_in_container
+    executor._run_in_container = MagicMock(return_value=b"hello")
+    
+    callback = AsyncMock()
+    await executor.add_task("print('hello')", callback)
+    
+    # 启动 worker 并在处理完一个任务后取消
+    worker_task = asyncio.create_task(executor.worker())
+    
+    # 等待队列为空
+    await executor.task_queue.join()
+    
+    # 验证结果
+    callback.assert_called_with("hello")
+    
+    # 取消 worker
+    worker_task.cancel()
+    try:
+        await worker_task
+    except asyncio.CancelledError:
+        pass
+
+@pytest.mark.asyncio
+async def test_worker_timeout(executor):
+    """测试 Worker 处理任务超时"""
+    # Mock _run_in_container to sleep longer than timeout
+    async def slow_run(*args):
+        await asyncio.sleep(0.2)
+        return b""
+    
+    # 我们不能直接 mock 同步方法让它异步 sleep，
+    # 因为 run_in_executor 会在线程中运行它。
+    # 这里我们 mock asyncio.wait_for 抛出 TimeoutError 可能会更容易，
+    # 但为了测试完整流程，我们可以让 _run_in_container 阻塞。
+    
+    # 实际上，我们可以 mock _run_in_container 抛出 asyncio.TimeoutError 
+    # (虽然它是在线程中运行，但 wait_for 会抛出这个异常)
+    # 不，wait_for 抛出 TimeoutError 是因为 future 没有在时间内完成。
+    
+    # 让我们简单地 mock _run_in_container 并让 wait_for 超时
+    executor.timeout = 0.01
+    executor._run_in_container = MagicMock(side_effect=lambda x: time.sleep(0.05))
+    
+    import time
+    
+    callback = AsyncMock()
+    await executor.add_task("print('hello')", callback)
+    
+    worker_task = asyncio.create_task(executor.worker())
+    await executor.task_queue.join()
+    
+    callback.assert_called_with(f"执行超时 (超过 {executor.timeout} 秒)。")
+    
+    worker_task.cancel()
+    try:
+        await worker_task
+    except asyncio.CancelledError:
+        pass
+
+@pytest.mark.asyncio
+async def test_worker_docker_errors(executor):
+    """测试 Worker 处理 Docker 错误"""
+    # ImageNotFound
+    executor._run_in_container = MagicMock(side_effect=docker.errors.ImageNotFound("Image not found"))
+    callback = AsyncMock()
+    await executor.add_task("code", callback)
+    
+    worker_task = asyncio.create_task(executor.worker())
+    await executor.task_queue.join()
+    callback.assert_called_with(f"执行失败：沙箱基础镜像 '{executor.sandbox_image}' 不存在，请联系管理员构建。")
+    worker_task.cancel()
+    try: await worker_task
+    except: pass
+
+    # ContainerError
+    executor._run_in_container = MagicMock(side_effect=docker.errors.ContainerError(
+        "container", 1, "cmd", "image", b"Error output"
+    ))
+    callback = AsyncMock()
+    await executor.add_task("code", callback)
+    
+    worker_task = asyncio.create_task(executor.worker())
+    await executor.task_queue.join()
+    callback.assert_called_with("代码执行出错:\nError output")
+    worker_task.cancel()
+    try: await worker_task
+    except: pass
+
+def test_run_in_container_success(executor):
+    """测试 _run_in_container 成功"""
+    mock_container = MagicMock()
+    mock_container.wait.return_value = {"StatusCode": 0}
+    mock_container.logs.side_effect = [b"output", b""] # stdout, stderr
+    
+    executor.docker_client.containers.create.return_value = mock_container
+    
+    result = executor._run_in_container("print('hello')")
+    
+    assert result == b"output"
+    mock_container.start.assert_called_once()
+    mock_container.remove.assert_called_with(force=True)
+
+def test_run_in_container_failure(executor):
+    """测试 _run_in_container 失败（非零退出码）"""
+    mock_container = MagicMock()
+    mock_container.wait.return_value = {"StatusCode": 1}
+    mock_container.logs.side_effect = [b"", b"Error"] # stdout, stderr
+    
+    executor.docker_client.containers.create.return_value = mock_container
+    
+    with pytest.raises(docker.errors.ContainerError):
+        executor._run_in_container("bad code")
+    
+    mock_container.remove.assert_called_with(force=True)
+
+def test_run_in_container_no_client(executor):
+    """测试 _run_in_container 无客户端"""
+    executor.docker_client = None
+    with pytest.raises(docker.errors.DockerException):
+        executor._run_in_container("code")