Fix Babel loose mode warnings

- Add @babel/plugin-transform-private-property-in-object with loose: true
- Add @babel/plugin-transform-private-methods with loose: true
- Match loose mode setting with @babel/plugin-transform-class-properties

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

.babelrc

@@ -12,6 +12,8 @@
     "transform-vue-jsx",
     "@babel/plugin-syntax-dynamic-import",
     ["@babel/plugin-proposal-decorators", { "legacy": true }],
-    ["@babel/plugin-proposal-class-properties", { "loose": true }]
+    ["@babel/plugin-proposal-class-properties", { "loose": true }],
+    ["@babel/plugin-transform-private-property-in-object", { "loose": true }],
+    ["@babel/plugin-transform-private-methods", { "loose": true }]
   ]
 }