AuditLogger API
logger = AuditLogger("audit.db")
# Log an entry
logger.log(agent_did, action="sign_message", result="success",
peer_did=peer_did, metadata={"algo": "ML-DSA-65"})
# Query
entries = logger.query(agent_did=agent_did, limit=50)
# Verify chain
from trusthub.audit.integrity import verify_audit_chain
is_valid, errors = verify_audit_chain(logger)