Add live sync heartbeat for status decay

server/lib/liveSync.test.ts

@@ -1,6 +1,18 @@
-import { describe, expect, it } from 'vitest';
+import fs from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+import { afterEach, describe, expect, it, vi } from 'vitest';
 import { fallbackDashboardSnapshot } from '../../src/data/mockDashboard';
-import { buildSnapshotPatch } from './liveSync';
+import { AuthService } from './auth';
+import { buildRuntimePaths } from './config';
+import { LiveSyncServer, buildSnapshotPatch } from './liveSync';
+
+const cleanupDirs: string[] = [];
+
+afterEach(async () => {
+  vi.useRealTimers();
+  await Promise.all(cleanupDirs.splice(0).map((dir) => fs.rm(dir, { recursive: true, force: true })));
+});
 
 describe('buildSnapshotPatch', () => {
   it('returns only changed top-level dashboard sections', () => {
@@ -27,4 +39,33 @@ describe('buildSnapshotPatch', () => {
       system: fallbackDashboardSnapshot.system,
     });
   });
+
+  it('refreshes snapshots on the heartbeat even without file changes', async () => {
+    vi.useFakeTimers();
+
+    const rootDir = await fs.mkdtemp(path.join(os.tmpdir(), '3proxy-ui-live-sync-'));
+    cleanupDirs.push(rootDir);
+
+    const snapshotReader = vi.fn().mockResolvedValue(fallbackDashboardSnapshot);
+    const server = new LiveSyncServer({
+      auth: new AuthService({
+        login: 'admin',
+        password: 'proxy-ui-demo',
+        ttlMs: 60_000,
+      }),
+      heartbeatMs: 50,
+      runtime: {} as never,
+      runtimePaths: buildRuntimePaths(rootDir),
+      snapshotReader,
+      store: {} as never,
+    });
+
+    await server.initialize();
+    expect(snapshotReader).not.toHaveBeenCalled();
+
+    await vi.advanceTimersByTimeAsync(50);
+    expect(snapshotReader).toHaveBeenCalledTimes(1);
+
+    server.close();
+  });
 });