feat: add and use loading

src/locales/lang/en.ts

@@ -52,6 +52,7 @@ const msg = {
   endpoint: "Endpoint",
   instance: "Instance",
   create: "Create",
+  loading: "Loading",
   hourTip: "Select Hour",
   minuteTip: "Select Minute",
   secondTip: "Select Second",

src/locales/lang/zh.ts

@@ -50,6 +50,7 @@ const msg = {
   layer: "层",
   endpoint: "端点",
   create: "新建",
+  loading: "加载中",
   hourTip: "选择小时",
   minuteTip: "选择分钟",
   secondTip: "选择秒数",