This is a follow-up to commit 8782619822.
* modules/rosenthal/services/child-error.scm (home-wakapi-shepherd-service)
* modules/rosenthal/services/mail.scm (home-goimapnotify-shepherd): Use
yaml-file.
* modules/rosenthal/utils/serializers/ini.scm: New file.
* modules/rosenthal/utils/serializers/utils.scm: New file.
* modules/rosenthal/utils/serializers/yaml.scm: New file.
* modules/rosenthal/utils/home-services-utils.scm: Delete file.
* modules/rosenthal/services/child-error.scm (home-wakapi-shepherd-service):
Use the new serializer.
* modules/rosenthal/services/web.scm (misskey-oci-containers): Likewise.
* modules/rosenthal/services/child-error.scm (%cloudflare-tunnel-accounts):
New variable.
(cloudflare-tunnel-service-type)[extensions]: Add it.
(cloudflare-tunnel-shepherd-service)[start]: Use the new user.