Adds the tamper-evident event stream that makes every DV auditable. Each
measurable moment is appended as one JSON object per line to an append-only
output/sor-runs/<ts>/events.jsonl over the closed vocabulary {consent_request,
consent_accept, consent_reject, circuit_build, hop_add, bridge_forward,
churn_kill, churn_spawn, rebuild_start, rebuild_done}; on close the file is
SHA-256'd and the digest is sealed exactly once into manifest.json (the single
sanctioned None->hash completion of the manifest).
Records carry only metadata (fingerprints, byte counts, latencies, decisions),
never message plaintext, so the zero-knowledge relay property is preserved. The
deterministic replay_fixture_circuit emits a seed-driven event stream with no
engine, socket, or traffic (containment-safe) and is the basis of
instrument-validation gate item 6.
- cmd_chat/sor/events.py: EventLog (append-only, per-record schema),
replay_fixture_circuit, replay_and_seal.
- cmd_chat/sor/provenance.py: seal_manifest (seal-once events SHA + stop ts).
- tests: replay -> schema-valid JSONL whose SHA matches the manifest;
append-only (original prefix byte-identical after further appends);
seed-determinism modulo timestamps; seal-once immutability.
Live emit wiring into the _sor handlers lands with R4/R5.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>