Make verification proof contracts match native artifact capabilities

A native artifact endpoint does not by itself make an outcome verifiable. The investigator must open the artifact, and the evidence adapter must expose an eligible proof type with explicit scope. Audit both when an evaluator repeatedly stops at lifecycle state despite available original artifacts.

For source implementation, complete native merged changes can establish represented source changes after exact repository, PR, immutable head/base and native event binding. Keep per-file evidence IDs and semantic relevance review. Check patch completeness against native hunk/addition/deletion counts; redacted, incomplete or mismatched changes stay context. This proof cannot establish runtime behavior, test execution, deployment, unseen requirements or persistent incompletion. A conservative all-files contract can also leave large or partially available PRs unverified; that is a coverage limit, not evidence of failure.