fix(primer): refresh Codex usage before primer and allow 1% fresh accounts

Codex primer was skipping with no_eligible_accounts because it read a
stale usage cache and required exactly 0% usage. Re-query usage right
before the primer call and treat freshly-reset 0~1% accounts as eligible
so the 5h window can be anchored at the fixed KST slot. Also hold new
Codex-owner turns at fresh usage until the next primer slot.

Co-Authored-By: Claude Opus 4 <noreply@anthropic.com>

src/usage-primer.test.ts

@@ -0,0 +1,77 @@
+import { describe, expect, it, vi } from 'vitest';
+
+const callOrder: string[] = [];
+
+const refreshAllCodexAccountUsage = vi.fn(async () => {
+  callOrder.push('refreshAll');
+  return { rows: [], fetchedAt: '2026-06-01T00:00:00.000Z' };
+});
+const refreshActiveCodexUsage = vi.fn(async () => {
+  callOrder.push('refreshActive');
+  return { rows: [], fetchedAt: '2026-06-01T00:00:01.000Z' };
+});
+const runCodexWarmupCycle = vi.fn(async () => {
+  callOrder.push('warmup');
+  return { status: 'warmed', accountIndex: 0 };
+});
+
+vi.mock('./config.js', () => ({
+  CODEX_WARMUP_CONFIG: {
+    enabled: false,
+    prompt: 'Reply exactly OK. Do not run tools.',
+    model: 'gpt-5.5',
+    intervalMs: 300_000,
+    minIntervalMs: 18_300_000,
+    staggerMs: 1_800_000,
+    maxUsagePct: 0,
+    maxD7UsagePct: 0,
+    commandTimeoutMs: 120_000,
+    failureCooldownMs: 21_600_000,
+    maxConsecutiveFailures: 2,
+  },
+}));
+
+vi.mock('./logger.js', () => ({
+  logger: {
+    debug: vi.fn(),
+    info: vi.fn(),
+    warn: vi.fn(),
+    error: vi.fn(),
+  },
+}));
+
+vi.mock('./token-rotation.js', () => ({
+  getAllTokens: vi.fn(() => []),
+}));
+
+vi.mock('./codex-usage-collector.js', () => ({
+  refreshAllCodexAccountUsage,
+  refreshActiveCodexUsage,
+}));
+
+vi.mock('./codex-warmup.js', () => ({
+  runCodexWarmupCycle,
+}));
+
+describe('usage-primer', () => {
+  it('refreshes Codex usage before primer selection and allows 1% fresh usage', async () => {
+    callOrder.length = 0;
+    refreshAllCodexAccountUsage.mockClear();
+    refreshActiveCodexUsage.mockClear();
+    runCodexWarmupCycle.mockClear();
+
+    const { runCodexPrimerCycle } = await import('./usage-primer.js');
+    await runCodexPrimerCycle();
+
+    expect(callOrder).toEqual(['refreshAll', 'refreshActive', 'warmup']);
+    expect(runCodexWarmupCycle).toHaveBeenCalledWith(
+      expect.objectContaining({
+        enabled: true,
+        minIntervalMs: 18_000_000,
+        maxUsagePct: 1,
+        maxD7UsagePct: 100,
+      }),
+      { ignoreZeroUsageWindow: true },
+    );
+  });
+});