`matrix-media-repo` is the only role that seems incompatible with the
changes introduced by Traefik v3, due to its use of `PathPrefix` with
regular expressions in a few places.

Regular expressions should now be used with `PathRegexp`, not
`PathPrefix`. Furthermore, they should follow the Golang regexp syntax,
as described in the migration guide:
https://doc.traefik.io/traefik/migration/v2-to-v3-details/#dynamic-configuration-changes

Related to 0241c71a4c

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/3270#issuecomment-2143782962

With this change, it should be possible for people to adjust the Docker
dependency from `docker.service` to something else (e.g. `pkg-ContainerManager-dockerd.service`),
or to completely eliminate it by setting `devture_systemd_docker_base_docker_service_name` to an empty string.

This makes it easier for people to use the playbook against a Synology DSM server.

Related to 2c40dfd9b8 (commitcomment-142588565)

It seems like there's no published container image with a 2.52.1 tag
and there's also no Prometheus 2.52.1 release yet.

Related to c1241761fd (commitcomment-141351388)

This new version makes the mail spool persistent, so that exim can be
restarted without losing queued messages.

* add keydb as redis replacement

* sort requirements