Record TrustOps receipts and factsheet evidence

[mdheller]

Purpose

Add ledger support for TrustOps evidence receipts created by the TrustOps Fabric vertical slice.

Upstream contract PR: SocioProphet/functional-model-surfaces#9
Runtime issue: SocioProphet/prophet-platform#398

Scope

• Add examples and validation path for trustops-receipt.v1 records.
• Define ledger record categories for robustness, fairness, explanation, uncertainty, ranking fairness, RAG trust, dataset risk, and agent trust.
• Preserve signed/redacted evidence refs rather than raw sensitive data.
• Support generated factsheet refs derived from receipts, not manually maintained prose.
• Ensure promotion, rollback, revocation, and waiver records can cite TrustOps receipt IDs.

Acceptance criteria

• A sample ART smoke receipt can be stored as model/service evidence.
• Ledger record links subject, runner, policy decision, evidence refs, provenance, and receipt digest.
• Revocation/rollback records can reference failed TrustOps gates.
• No raw regulated/customer/personal data is required to record the receipt.

[mdheller]

Update after PR #21 merge.

TrustOps receipt ledger support is now landed as an evidence-only ledger record.

Merged surface:

• schemas/trustops-receipt-ledger-record.v0.1.schema.json
• tools/validate_trustops_receipt_ledger_record.py
• examples/trustops-receipt-ledger-record.example.json
• examples/trustops-receipt-ledger-record.raw-sensitive.invalid.json
• examples/trustops-receipt-ledger-record.control-plane.invalid.json
• docs/trustops-receipt-ledger-records.md
• Makefile target validate-trustops-receipts

Boundary encoded:

• TrustOps receipt remains evidence.
• Guardrail Fabric remains the runtime-control decision plane.
• Agent Registry remains the authority mutation decision plane.
• Model Governance Ledger remains the evidence and lifecycle ledger.
• Ledger records cannot perform runtime action or mutate authority.
• Ledger records reject raw sensitive data and raw data export.
• Evidence refs must be redacted evidence:// refs, not raw data handles.
• Restrictive policy decisions cite downstream control-plane refs rather than performing the action directly.

This advances #11 without turning the ledger into a control plane.