Document the trip publish-toggle cache-invalidation finding: an in-place
trip.md `published` edit under cache.check.method: folder + APCu driver stays
stale because the folder checksum is unchanged AND the web APCu store is
unreachable by a CLI clearcache — fixed with apcu_clear_cache() from the web
request. Cross-link the sibling grav-deleteall doc (the create/delete case) as
necessary-but-not-sufficient here, and add the Published/Draft trip status
concept to CONCEPTS.md.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Mpdu3Dt1iVoozHwAMyjrbn
