Fix telemetry shutdown noise and improve token usage diagnostics (#444)

Co-authored-by: zuolingxuan <zuolingxuan@bytedance.com>

tests/unit/models-usage-history.test.ts

@@ -0,0 +1,68 @@
+import { describe, expect, it } from 'vitest';
+import {
+  filterUsageHistoryByWindow,
+  groupUsageHistory,
+  type UsageHistoryEntry,
+} from '@/pages/Models/usage-history';
+
+function createEntry(day: number, totalTokens: number): UsageHistoryEntry {
+  return {
+    timestamp: `2026-03-${String(day).padStart(2, '0')}T12:00:00.000Z`,
+    sessionId: `session-${day}`,
+    agentId: 'main',
+    model: 'gpt-5',
+    inputTokens: totalTokens,
+    outputTokens: 0,
+    cacheReadTokens: 0,
+    cacheWriteTokens: 0,
+    totalTokens,
+  };
+}
+
+describe('models usage history helpers', () => {
+  it('keeps all day buckets instead of truncating to the first eight', () => {
+    const entries = Array.from({ length: 12 }, (_, index) => createEntry(index + 1, index + 1));
+
+    const groups = groupUsageHistory(entries, 'day');
+
+    expect(groups).toHaveLength(12);
+    expect(groups[0]?.totalTokens).toBe(1);
+    expect(groups[11]?.totalTokens).toBe(12);
+  });
+
+  it('limits model buckets to the top eight by total tokens', () => {
+    const entries = Array.from({ length: 10 }, (_, index) => ({
+      ...createEntry(index + 1, index + 1),
+      model: `model-${index + 1}`,
+    }));
+
+    const groups = groupUsageHistory(entries, 'model');
+
+    expect(groups).toHaveLength(8);
+    expect(groups[0]?.label).toBe('model-10');
+    expect(groups[7]?.label).toBe('model-3');
+  });
+
+  it('filters the last 30 days relative to now instead of calendar month boundaries', () => {
+    const now = Date.parse('2026-03-12T12:00:00.000Z');
+    const entries = [
+      {
+        ...createEntry(12, 12),
+        timestamp: '2026-03-12T12:00:00.000Z',
+      },
+      {
+        ...createEntry(11, 11),
+        timestamp: '2026-02-11T12:00:00.000Z',
+      },
+      {
+        ...createEntry(10, 10),
+        timestamp: '2026-02-10T11:59:59.000Z',
+      },
+    ];
+
+    const filtered = filterUsageHistoryByWindow(entries, '30d', now);
+
+    expect(filtered).toHaveLength(2);
+    expect(filtered.map((entry) => entry.totalTokens)).toEqual([12, 11]);
+  });
+});