Why: batch update leaked AGENT_SYSTEM_INSTANCE_ID/DBREF from one service
to the next, and RDM artifacts without the identity CLI were stopped and
overwritten before their startup identity refusal surfaced, leaving
rdm1/rdmcand in a mixed registration-vs-artifact state (2026-10-12).
Evidence: make test-governance 217 OK; tests.test_svc_identity and
tests.test_svc_precheck green; rows recorded in the task card.
Impact: env_config resets identity env per service; capability probe is
timeout-guarded and rejects serve-shaped output; identity ensure moves
to adoption/init (bare start is verify-only); deploy builds and gates
candidates before stopping the old service (refuses identityless
candidates, completes missing identity rows via the candidate); update
runs svc_manifest_migrate like every other lifecycle entry.
Refs: .task/feature-svc-identity-u1.md; user root-cause report 2026-10-12.