✨ feat(jvm-ui): 完善 JVM 工作台与监控入口

- 新增 JVM 持续监控仪表盘、图表、状态卡和详情面板

- 统一概览、资源浏览、审计页面的 JVM 工作台布局

- Sidebar 和 TabManager 支持监控入口、诊断入口兜底和上下文切换

- 补充前端状态模型、展示文案和组件回归测试

frontend/src/store.test.ts

@@ -119,6 +119,51 @@ describe('store appearance persistence', () => {
     expect(useStore.getState().connections[0]?.config.password).toBe('secret');
   });
 
+  it('preserves JVM Arthas diagnostic config when replacing saved connections', async () => {
+    const { useStore } = await importStore();
+
+    useStore.getState().replaceConnections([
+      {
+        id: 'jvm-1',
+        name: 'Orders JVM',
+        config: {
+          id: 'jvm-1',
+          type: 'jvm',
+          host: '127.0.0.1',
+          port: 9010,
+          user: '',
+          jvm: {
+            allowedModes: ['jmx'],
+            preferredMode: 'jmx',
+            diagnostic: {
+              enabled: true,
+              transport: 'arthas-tunnel',
+              baseUrl: 'http://127.0.0.1:7777',
+              targetId: 'gonavi-local-test',
+              apiKey: 'diag-token',
+              allowObserveCommands: true,
+              allowTraceCommands: true,
+              allowMutatingCommands: false,
+              timeoutSeconds: 20,
+            },
+          },
+        },
+      },
+    ]);
+
+    expect(useStore.getState().connections[0]?.config.jvm?.diagnostic).toEqual({
+      enabled: true,
+      transport: 'arthas-tunnel',
+      baseUrl: 'http://127.0.0.1:7777',
+      targetId: 'gonavi-local-test',
+      apiKey: 'diag-token',
+      allowObserveCommands: true,
+      allowTraceCommands: true,
+      allowMutatingCommands: false,
+      timeoutSeconds: 20,
+    });
+  });
+
   it('keeps legacy global proxy password during hydration until explicit cleanup', async () => {
     storage.setItem('lite-db-storage', JSON.stringify({
       state: {