feat(frontend): 增强连接树搜索与资源管理器布局

为连接管理页左侧标签树新增独立搜索能力，支持命中节点、
祖先链路过滤与自动展开，提升大规模连接下的检索效率。

同步优化树头部为资源管理器式布局，并强化节点计数高亮；
补充中英日文案，同时归档并更新 helloagents 记录。

packages/frontend/src/locales/en-US.json

@@ -364,6 +364,11 @@
     "status": {
       "never": "Never"
     },
+    "scopeExplorerTitle": "Tag Explorer",
+    "scopeHintCompact": "Tree nodes are grouped by tag path",
+    "scopeTreeSearch": "Search tag tree...",
+    "scopeSearchMode": "Matched paths are expanded",
+    "scopeTreeNoMatch": "No matching tree nodes",
     "untaggedGroup": "Untagged",
     "noUntaggedConnections": "No untagged connections found."
   },
@@ -1097,6 +1102,9 @@
     "height": "Height",
     "reconnect": "Reconnect",
     "retry": "Retry",
+    "reset": "Reset",
+    "expandAll": "Expand All",
+    "collapseAll": "Collapse All",
     "sortAscending": "Ascending",
     "sortDescending": "Descending",
     "restore": "Restore",