Why: main landed fix-svc-dsn-reuse-dbref (reuse-path dbref restore, env-DSN
aware precheck, DSN_ENV scoping) for the same restart-DSN incident; the
approved recovery plan is its superset and replaces those mechanisms with
resolve_db_config + recoverable svc.env keys + refuse-on-invalid semantics.
Evidence: tests/test_svc_precheck.py ported to the new units (18 cases green,
same scenario matrix; broken-dbref expectation updated to refusal per the
approved plan); tests/test_svc.py 11 cases green; bash -n OK.
Impact: conflict hunks resolved toward the unified resolver; main's source
guard at the script tail restored; agent_listen_rejected kept as a pure
predicate (used by the start precheck and the governance tests).
Refs: main 7acf318 (PR #317); task card .task/feature-svc-db-config-recover.md.
weichen
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