fix: 修复 Agent 状态与监控大屏

frontend/src/locales/en-US.json

@@ -4110,6 +4110,14 @@
         "batchUninstall": "Batch Uninstall",
         "deploying": "Deploying",
         "chart": "Chart",
+        "overview": {
+          "totalHosts": "Total Hosts",
+          "online": "Online",
+          "offline": "Offline",
+          "notInstalled": "Not Installed",
+          "avgCpu": "Average CPU",
+          "avgMemory": "Average Memory"
+        },
         "toast": {
           "installed": "Agent installation submitted, running in background…",
           "installFailed": "Installation failed",