Disambiguates all overloaded terms in the codebase: Person vs AppUser,
Chronik (internal) vs Aktivität (user-facing), TranscriptionBlock polygon
vs bounding box, DocumentVersion append-only convention, OcrJob lifecycle,
SenderModel as persistent entity, Audit log DB-layer caveat, and more.
Includes Pending Terms section for audit follow-ups (#388–#392).
Refs #397
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>