docs(roadmap): Milestone 4 — evidence types beyond execution

docs/15-milestones.md

@@ -12,9 +12,9 @@ bullets into issues. Each bullet is scoped to concrete files.
       (PyPI); machine-readable registry at `schemas/index.json`.
 - [x] Conformance harness: every schema well-formed, refs resolve, valid/invalid
       fixtures per schema (`tests/conformance.py`).
-- [ ] Publish `@wasmagent/protocol@0.1.0` to npm and `wasmagent-protocol==0.1.0`
+- [x] Publish `@wasmagent/protocol@0.1.0` to npm and `wasmagent-protocol==0.1.0`
       to PyPI; record both in the org release ledger.
-- [ ] Strip local schema copies from `wasmagent-js` (`packages/compliance/schemas/`,
+- [x] Strip local schema copies from `wasmagent-js` (`packages/compliance/schemas/`,
       `packages/core/src/ranking/schemas/rollout-wire.schema.json`) and depend on
       the npm package.
 - [ ] Strip local schema copies from `trace-pipeline` (`schemas/*.schema.json`)
@@ -25,7 +25,7 @@ bullets into issues. Each bullet is scoped to concrete files.
 
 - [ ] Migrate `wasmagent-proxy` Rust `aep-core` types to generate from / validate
       against `schemas/aep/aep-record.schema.json`.
-- [ ] Point `wasmagent-train-replay` `EpochEvidenceBundle` at the shared AEP
+- [x] Point `wasmagent-train-replay` `EpochEvidenceBundle` at the shared AEP
       record schema for its evidence envelope.
 - [ ] Map `open-agent-audit` `schemas/v0.1/*` adapter onto the canonical AEP
       record; document the version-skew adapter.
@@ -40,3 +40,20 @@ bullets into issues. Each bullet is scoped to concrete files.
       Python `TypedDict`s so consumers get types, not just validation.
 - [ ] Add a conformance test suite consumers can run against their own emitters
       (`aep-conformance` fixtures published in the package).
+
+## Milestone 4 — Evidence types beyond execution
+
+AEP today covers execution evidence (`aep-record`). Memory / Replay / Checkpoint
+/ Artifact each enter the protocol as a **new evidence record under AEP** sharing
+one signature envelope — not a rename to "ARP" (rejected: dilutes the provable
+positioning and forces an org-wide breaking rename). Each bullet below is a
+single self-contained schema deliverable; land one only after the runtime
+feature it describes is real (protocol is sedimented, not designed up front).
+
+- [ ] Add `schemas/aep/evidence-envelope.schema.json` — shared base (schema_version, signature{alg,key_id,sig}, trace_id, created_at_ms) that every evidence record `$ref`s; register in `schemas/index.json` with a valid+invalid fixture under `tests/fixtures/`.
+- [ ] Refactor `schemas/aep/aep-record.schema.json` to `$ref` the shared `evidence-envelope` for its signature/version fields; keep field set identical (no breaking change), add fixture proving equivalence.
+- [ ] Add `schemas/aep/memory-evidence.schema.json` — tamper-evident memory read/write record (keys: mem_ref, op enum[read,write], digest, prior_digest, timestamp_ms); register in index + valid/invalid fixtures.
+- [ ] Add `schemas/aep/replay-evidence.schema.json` — deterministic-replay attestation (keys: run_id, seed, input_digests[], output_digest, engine_version); register in index + valid/invalid fixtures.
+- [ ] Add `schemas/aep/checkpoint-evidence.schema.json` — signed checkpoint/fork record (keys: checkpoint_id, parent_run_id, fork_of, state_digest, created_at_ms); register in index + valid/invalid fixtures.
+- [ ] Add `schemas/aep/artifact-attestation.schema.json` — produced-artifact provenance (keys: artifact_uri, digest, produced_by_run_id, tool_name, signature); register in index + valid/invalid fixtures.
+- [ ] Update README + `docs/CONTRACT-CHANGE-PROCESS.md` to list the new evidence types and their consumer repos once each ships.