`new Date(ms).toUTCString()` was refused (SC2020). It now lowers to a
runtime formatter over the stored time value with V8's output: "Www, DD
Mmm YYYY HH:mm:ss GMT" in UTC, a leading "-" and at least four digits for
negative years, and "Invalid Date" for an invalid time value.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>