The locals.user.groups.some(...WRITE_ALL) derivation was copy-pasted across
the persons directory, persons review and the two document loaders touched by
this PR. Extract a single tested hasWriteAll(locals) helper in
$lib/shared/server and reuse it, removing the ad-hoc casts.
Refs #667
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
