* In-app Back arrow is now deterministic on deep links: if there's in-app history
it pops (history.back); otherwise it navigates to the parent screen (game →
selection → hub) instead of leaving the site. Device Back stays native.
* Canonicalize ?game/?v: unknown game → hub; an invalid v for the game (e.g.
word&v=large or wordsearch&v=5) → the game's default, via replaceState so the
URL is clean and local-storage keys/status match. Derived variant/size are also
clamped so a bad URL can never crash the game with an invalid variant.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
thejayman77
1dda91fd96