fix(infra): restore official production volume and repair directus snapshot

- Hardened docker-compose.yml to use klz-cablescom_directus-db-data volume
- Added mandatory 'relations: []' key to Directus snapshot.yaml
- Aligned internal network mappings for db connectivity

directus/schema/snapshot.yaml

@@ -224,4 +224,6 @@ systemFields:
     schema:
       is_indexed: true
 
+relations: []
+