catalog: omit the wall-clock-derived Countdown.targetDate default so the generated catalog (and drift test) no longer flip daily

Add a date-independence test (freezes Date at two different days via a preload).

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

craft/src/sitesmith/catalog.drift.test.ts

@@ -26,8 +26,11 @@ const craftRoot: string = path.resolve(decodeURIComponent(new URL('.', import.me
 const committedPath: string = proc.env.SITESMITH_CATALOG_FILE
   ?? path.resolve(craftRoot, '../../whp/web-files/libs/sitesmith-catalog.generated.json');
 
-function regenerate(): string {
-  return execFileSync(proc.execPath, ['scripts/gen-sitesmith-catalog.mjs', '--stdout'], {
+function regenerate(fakeNow?: string): string {
+  const args = ['scripts/gen-sitesmith-catalog.mjs', '--stdout'];
+  if (fakeNow) args.unshift('-r', path.join(craftRoot, 'scripts/fake-date-preload.cjs'));
+  return execFileSync(proc.execPath, args, {
+    env: fakeNow ? { ...proc.env, FAKE_NOW: fakeNow } : proc.env,
     cwd: craftRoot, encoding: 'utf8', maxBuffer: 64 * 1024 * 1024, timeout: 120_000,
   });
 }
@@ -47,6 +50,14 @@ describe('sitesmith catalog', () => {
     expect(fresh).toBe(committed);
   }, 130_000);
 
+  test('catalog is date-independent (Countdown default date is volatile and must not leak in)', () => {
+    const a = regenerate('2026-12-01T12:00:00Z');
+    const b = regenerate('2027-03-09T12:00:00Z');
+    expect(a).toBe(b);
+    expect(JSON.parse(a).components.Countdown.props.targetDate.default).toBeUndefined();
+    expect(a).not.toMatch(/"\d{4}-\d{2}-\d{2}"/);
+  }, 130_000);
+
   test('catalog covers every resolver component, with derived facts', () => {
     const cat = JSON.parse(regenerate());
     const resolver = fs.readFileSync(path.join(craftRoot, 'src/components/resolver.ts'), 'utf8');