✨ 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/utils/jvmSidebarActions.test.ts

@@ -0,0 +1,64 @@
+import { describe, expect, it } from "vitest";
+
+import {
+  buildJVMDiagnosticActionDescriptor,
+  buildJVMMonitoringActionDescriptors,
+} from "./jvmSidebarActions";
+
+describe("jvmSidebarActions", () => {
+  it("builds direct JVM monitoring entries from probed provider capabilities", () => {
+    expect(
+      buildJVMMonitoringActionDescriptors("conn-1", [
+        { mode: "jmx" },
+        { mode: "endpoint" },
+        { mode: "jmx" },
+      ]),
+    ).toEqual([
+      {
+        key: "conn-1-jvm-monitoring-jmx",
+        title: "持续监控 · JMX",
+        providerMode: "jmx",
+      },
+      {
+        key: "conn-1-jvm-monitoring-endpoint",
+        title: "持续监控 · Endpoint",
+        providerMode: "endpoint",
+      },
+    ]);
+  });
+
+  it("skips providers that cannot be browsed when building monitoring entries", () => {
+    expect(
+      buildJVMMonitoringActionDescriptors("conn-1", [
+        { mode: "jmx", canBrowse: true },
+        { mode: "agent", canBrowse: false },
+      ]),
+    ).toEqual([
+      {
+        key: "conn-1-jvm-monitoring-jmx",
+        title: "持续监控 · JMX",
+        providerMode: "jmx",
+      },
+    ]);
+  });
+
+  it("builds diagnostic entry independently from provider probing", () => {
+    expect(
+      buildJVMDiagnosticActionDescriptor("conn-1", {
+        enabled: true,
+        transport: "arthas-tunnel",
+      }),
+    ).toEqual({
+      key: "conn-1-jvm-diagnostic",
+      title: "诊断增强 · Arthas Tunnel",
+      transport: "arthas-tunnel",
+    });
+
+    expect(
+      buildJVMDiagnosticActionDescriptor("conn-1", {
+        enabled: false,
+        transport: "agent-bridge",
+      }),
+    ).toBeNull();
+  });
+});