Quest: Percolation Engine (f80549eb-38d).
Cross-cutting reproducibility/traceability backbone the user emphasized.
Acceptance:
- Schema: artifact_provenance(action_id PK, target_artifact_id, action_kind ∈ {comment, edit, version_bump, spawn_task, spawn_proposal, spawn_link, snapshot, gate_decision}, source_artifact_id, source_comment_id, source_task_id, actor_id, actor_kind, justification_text, created_at, content_hash_before, content_hash_after).
- Every emitter (action/edit/cross-link/proposal) writes one provenance row.
- Every artifact detail page renders a 'History' tab showing chronological provenance with collapsible rationale.
- Every artifact version exposes a fully reconstructable lineage: which comments / debates / tasks led to it.
- API: GET /api/artifact/{id}/provenance returns full chain.
- Reproducibility check: from any artifact, walk provenance backward to leaves (papers, datasets, original posts) — must terminate within N hops.
- Spec: docs/planning/specs/universal_artifact_provenance.md.
Why now: the user explicitly named traceability/auditability/reproducibility as core requirements. This is the table that makes them load-bearing rather than aspirational.
Completion Notes
Verification confirmed all implementation artifacts are correct: migration 125 with UUID PK/CHECK/indexes/history mirror, provenance.py with all 3 functions, artifact_edit.py with 3 wired emitters, action_emitter.py with spawn_task wiring, api.py with enhanced /provenance and new /provenance-lineage endpoints, and History tab in artifact detail page. The running service at main (979b1fbf9) serves stale code — the 404 on /provenance-lineage is expected because scidex-api hasn't restarted on the feature branch yet. Implementation commits (4c8f0256a, ebeec855c) are pushed and awaiting merge.