fix(frontend): smooth realtime dashboard refreshes

app/game-frontend/test/latestRefreshQueue.test.ts

@@ -0,0 +1,30 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { createLatestRefreshQueue } from '../src/utils/latestRefreshQueue.ts';
+
+void test('coalesces an event burst into one final refresh without losing it', async () => {
+    const releases: Array<() => void> = [];
+    let runs = 0;
+    const queue = createLatestRefreshQueue(async () => {
+        runs += 1;
+        await new Promise<void>((resolve) => releases.push(resolve));
+    });
+
+    const first = queue.request();
+    assert.equal(queue.isRunning(), true);
+    const second = queue.request();
+    const third = queue.request();
+    assert.equal(second, first);
+    assert.equal(third, first);
+    assert.equal(runs, 1);
+
+    releases.shift()?.();
+    await new Promise<void>((resolve) => setImmediate(resolve));
+    assert.equal(runs, 2);
+
+    releases.shift()?.();
+    await first;
+    assert.equal(queue.isRunning(), false);
+    assert.equal(runs, 2);
+});