支持local_config启动 添加注册表description字段 (#13)

Closes #11

* Update README and MQTTClient for installation instructions and code improvements

* feat: 支持local_config启动
add: 增加对crt path的说明，为传入config.py的相对路径
move: web component

* add: registry description

---------

Co-authored-by: Harvey Que <Q-Query@outlook.com>

unilabos/app/web/utils/host_utils.py

@@ -0,0 +1,68 @@
+"""
+主机节点工具模块
+
+提供与主机节点相关的工具函数
+"""
+
+import time
+from typing import Dict, Any
+
+from unilabos.config.config import BasicConfig
+from unilabos.ros.nodes.presets.host_node import HostNode
+from unilabos.app.web.utils.action_utils import get_action_info
+
+
+def get_host_node_info() -> Dict[str, Any]:
+    """
+    获取主机节点信息
+
+    尝试获取HostNode实例并提取其设备、主题和动作客户端信息
+
+    Returns:
+        Dict: 包含主机节点信息的字典
+    """
+    host_info = {"available": False, "devices": {}, "subscribed_topics": [], "action_clients": {}}
+    if not BasicConfig.is_host_mode:
+        return host_info
+    # 尝试获取HostNode实例，设置超时为0秒
+    host_node = HostNode.get_instance(0)
+    if not host_node:
+        return host_info
+    host_info["available"] = True
+    host_info["devices"] = {
+        device_id: {
+            "namespace": namespace,
+            "is_online": f"{namespace}/{device_id}" in host_node._online_devices,
+            "key": f"{namespace}/{device_id}" if namespace.startswith("/") else f"/{namespace}/{device_id}",
+        }
+        for device_id, namespace in host_node.devices_names.items()
+    }
+    # 获取已订阅的主题
+    host_info["subscribed_topics"] = sorted(list(host_node._subscribed_topics))
+    # 获取动作客户端信息
+    for action_id, client in host_node._action_clients.items():
+        host_info["action_clients"] = {
+            action_id: get_action_info(client, full_name=action_id)
+        }
+
+    # 获取设备状态
+    host_info["device_status"] = host_node.device_status
+
+    # 添加设备状态更新时间戳
+    current_time = time.time()
+    host_info["device_status_timestamps"] = {}
+    for device_id, properties in host_node.device_status_timestamps.items():
+        host_info["device_status_timestamps"][device_id] = {}
+        for prop_name, timestamp in properties.items():
+            if timestamp > 0:  # 只处理有效的时间戳
+                host_info["device_status_timestamps"][device_id][prop_name] = {
+                    "timestamp": timestamp,
+                    "elapsed": round(current_time - timestamp, 2),  # 计算经过的时间（秒）
+                }
+            else:
+                host_info["device_status_timestamps"][device_id][prop_name] = {
+                    "timestamp": 0,
+                    "elapsed": -1,  # 表示未曾更新过
+                }
+
+    return host_info