X_SITEMAP_ENTRY_INVALID
Means
a sitemap entry carries a lastmod or a locale the sitemap cannot write
Typical cause
a prerender() entry (or a page handed to buildSitemap) has a lastmod that is not an ISO 8601 date with an explicit zone, or names a locale the app does not route
Fix
x verify --json after prerender() in the route file named in cause answers lastmod as a Date or an ISO 8601 string with a zone (row.updatedAt) and only routed locales in locales