feat(k8s): add defaults/main.yml, meta/main.yml for all 27 roles + 4 helm templates

- Added defaults/main.yml with production-ready values for all 27 Ansible roles
- Added meta/main.yml with role dependencies (DAG: prereq → namespaces → storage → traefik → cert-manager → services)
- Created 4 missing Helm templates: flink-deployment, kafka-cluster, smartapp-web, smartapp-api
- Fixed YAML syntax error in backup/tasks/main.yml (Velero backupStorageLocation)
- Updated README with domain list, dependencies diagram, and corrected Helm chart names
- All 81 YAML files pass validation

helms/roles/backup/tasks/main.yml

@@ -11,7 +11,7 @@
     values:
       configuration:
         backupStorageLocation:
-          name: default
+          - name: default
             provider: aws
             bucket: smart-city-backup
             config: