feat(linkedin-studio): SB-S1 ingest data layer — record grammar + content-id [skip-docs]
PublishedRecord file-per-post grammar (fixed 5-line header + --- sentinel +
verbatim body, no YAML) with parse∘serialize identity, and mintContentId =
sha256(VERBATIM body)[:12] — byte-identity dedup so two structurally-different
posts never collide (avoids the normalizeContent silent-data-loss path).
parsePublishedRecord rejects a published/ record whose provenance != published
(corruption signal). 10 grammar tests incl. the B1 edge battery (empty body,
body starting with ---, mid-text \n---\n, header-shaped first line) + 4 id tests.
Pure layer only; IO + CLI + voice-trainer wiring follow. brain 34→48 tests.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RigJBiRFNtFZKCz21qNbQ4