DR-025 — The corpus reframe: sources are evidence; authority is earned at promotion

“Source file” is three things, now separated: evidence bytes (inputs, per-binding retention class), the permanent provenance register (source_documents rows survive byte discard; citations degrade to the register, never orphan), and authoritative artefacts (promoted records + the OKF bundle — platform OUTPUTS). Two gates: a light binding gate (connect a source, assign retention class) and the authoritative knowledge-admission gate (record promotion + dedup/confidence; concept linter + publish gate) — human review is the launch posture, auto-apply earned per progressive trust. Refines DR-023. Evidence: S441 ratification board (R1–R8) + specs/id-138-corpus-durable-home/notes/user-feedback-on-corpus-durable-home-decision.md (migrated S507 out of canonical’s gitignored scratch — the S504 F1 lossy-provenance caveat no longer applies).