Build-an-X workflow that verifies locale-specific format rendering - dates (US `5/4/2026` vs ISO `2026-05-04` vs DE `04.05.2026` vs JP `2026/05/04`), numbers (US `1,234.56` vs DE `1.234,56` vs FR `1 234,56`), currencies (US `$1,234.56` vs JP `¥1,235` vs DE `1.234,56 €`), times, durations. Use when the product displays locale-sensitive data and the team needs assurance the formatting matches per-locale conventions.