Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/3090

Related to https://github.com/mautrix/signal/issues/422

* chore(deps): update signal bridge version + config

* style(deps): rename default note to self config variable

* Add to_json for additional safety

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Co-authored-by: Slavi Pantaleev <slavi@devture.com>

.. because matrix_mautrix_signal_version is used in other places
which do not expect it. For example: `matrix_mautrix_signal_container_image_self_build_branch`

Related to: https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/3041

0.23.1 no longer syncs groups properly, the solution is to use 0.23.2, which works as expected

* one var to control encryption across all bridges

* move var to matrix-base

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/2427

`metrics_enabled` should only expose the metrics locally, on the
container network, so that a local Prometheus can consume them.

Exposing them publicly should be done via a separate toggle (`metrics_proxying_enabled`).
This is how all other roles work, so this makes these mautrix roles consistent with the rest.

Fixes the following issue when trying to use the !pm <phone number> command: https://gitlab.com/signald/signald/-/issues/345

This paves the way for installing other roles into `roles/galaxy` using `ansible-galaxy`,
similar to how it's done in:

- https://github.com/spantaleev/gitea-docker-ansible-deploy
- https://github.com/spantaleev/nextcloud-docker-ansible-deploy

In the near future, we'll be removing a lot of the shared role code from here
and using upstream roles for it. Some of the core `matrix-*` roles have
already been extracted out into other reusable roles:

- https://github.com/devture/com.devture.ansible.role.postgres
- https://github.com/devture/com.devture.ansible.role.systemd_docker_base
- https://github.com/devture/com.devture.ansible.role.timesync
- https://github.com/devture/com.devture.ansible.role.vars_preserver
- https://github.com/devture/com.devture.ansible.role.playbook_runtime_messages
- https://github.com/devture/com.devture.ansible.role.playbook_help

We just need to migrate to those.