Freeze lab-tested PostgreSQL plugin engine

Extract PostgreSQL, Podman runtime and systemd lifecycle adapters while preserving existing lifecycle and scoring behavior. Update RPM layout and add guarded operator-run lab harnesses.

Record successful manual stop/start, promotion, demotion and rewind-only rejoin with pinned installed hashes. The unfenced lab does not validate automatic failover, Pacemaker-managed transitions or divergent-data rewind.

Validation: 103 offline tests, original-function differential checks, checksum manifest and whitespace checks passed.

refactored/managed-container.d/container.sh

@@ -37,8 +37,7 @@ as_service_user()
 
 service_running()
 {
-    as_service_user \
-        systemctl --user is-active --quiet "${SERVICE_NAME}"
+    mc_lifecycle_running "${SERVICE_NAME}"
 }
 
 container_running()
@@ -46,7 +45,7 @@ container_running()
     local state
 
     state="$(
-        as_service_user podman inspect \
+        mc_runtime_inspect \
             --format '{{.State.Running}}' \
             "${CONTAINER_NAME}" 2>/dev/null
     )" || return 1