Address review feedback: introduce a MajorMinorVersion type with
isMajorMinorVersion, rename majorMinorVersion to normaliseMajorMinorVersion,
and type ModInfo.factorioVersion as MajorMinorVersion so already-reduced
values are not re-reduced (ModPackViewPage uses mod.info.factorioVersion
directly). Reuse the single gameVersionRegExp in both GameVersionSchema and
normaliseGameVersion instead of duplicating the pattern.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>