PR #2117 — A Human Attestation for Legacy Job Provenance

The Broader Goal at the End of the Previous PR

PR #2116 retired the generic legacy adapter fallback while preserving the registered harness behavior. The related adapter conformance suite in #2081 was still waiting on the cross-harness provenance gate. The wider goal remains to make adapter contracts explicit and to require review evidence that can be traced to the jobs that performed the work.

Strategic Shifts in This PR (if any)

The provenance resolver now handles a fact that a new dispatch can record directly but an older dispatch cannot: whether its task type was explicitly selected. For job job-2a2b25fa, Nikhil confirmed that --task-type test was supplied. Synlynk should preserve that as a later human attestation, rather than writing it back into the historical manifest as if it had always been there.

What This PR Shipped

Migration 18 adds job_provenance_attestations, an append-only table tied to an exact job ID. synlynk provenance attest records the role, task type, derived purpose, operator attribution, rationale, and local CLI source. It requires the exact JOB_ID:ROLE:TASK_TYPE confirmation and rejects unknown operators, incompatible roles, and conflicts with existing job metadata.

The PR check accepts one compatible attestation only when dispatch purpose is missing, and still requires the exact PR/job cost link. Harness and model identity continue to come from the existing job/cost records. Reviewer actor, cross-harness, and cross-model checks remain in place. The historical task_type_explicit field stays unknown.

Focused verification passed: 59 provenance and migration tests, plus 16 existing PR-check tests. The implementation PR is open for independent review; the attestation for #2081 will be entered through the new CLI after the change is reviewed and merged.

Brainstorm Visuals Used

No brainstorm visual informed this change.

What This Achieved on the Path to Autonomy

Synlynk can now retain an explicit human decision about an incomplete legacy record without blurring it with dispatch telemetry. Review gates can use that decision while keeping job identity and PR links anchored to canonical records.

Strategic Note: The Goal at the End of This PR

The provenance path has a reviewed design, a supported attestation command, and fail-closed resolution. Once this PR passes independent review, apply the owner-confirmed dev / test attestation to #2081, rerun its gate, and resume the remaining #2062 checks.