Update ghcr.io/element-hq/synapse Docker tag to v1.115.0

Seems like `default` is not a supported value and will not
make the bridge autoconfigure itself with the correct prefix anymore.

A value of `default` would be taken literally.

f9705b3323 reworked the configuration and missed wiring
these to the existing variables.

Update maintenance-upgrading-services.md

We'be already been going against upstream defaults and have been
enabling backfilling for a few other bridges (Messenger, Instagram, Telegram, Twitter).

Now I'm enabling backfilling by default for the remaining ones, for
consistency.

Related to:
- https://github.com/mautrix/gmessages/releases/tag/v0.5.0
- https://mau.fi/blog/2024-09-mautrix-release/

It seems like the new version does not support a `/metrics` endpoint.
We skip keep the Ansible variables, but they're not doing anything.

Related to:
- https://github.com/mautrix/meta/releases/tag/v0.4.0
- https://mau.fi/blog/2024-09-mautrix-release/

It seems like the new version does not support a `/metrics` endpoint.
We skip keep the Ansible variables, but they're not doing anything.

While working on upgrading the Meta bridges to bridgev2, I've noticed
that {% raw %} and {% endraw %} on lines like that (immediately
preceding `username_template` may cause YAML indentation issues.

Update dock.mau.dev/mautrix/signal Docker tag to v0.7.1

Update dock.mau.dev/mautrix/slack Docker tag to v0.1.1

Update ajbura/cinny Docker tag to v4.2.1

Synapse-Admin: Add UI option to block deleted rooms from being rejoined

* Added an example of fronting the playbook's integrated Traefik reverse-proxy with the existing Caddy container (not the `apt-get` or `yum` installed Caddy).  Helpful for folks who have an existing server with a Caddy container already serving multiple applications.

* Update examples/reverse-proxies/caddy2-in-container/README.md

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

* Update examples/reverse-proxies/caddy2-in-container/README.md

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

* Update examples/reverse-proxies/caddy2-in-container/README.md

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

* Code formatted, linted with yamllint

* README.md updated

* docs/configuring-playbook-own-webserver-caddy.md removed

---------

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

Update matrixdotorg/dendrite-monolith Docker tag to v0.13.8

Update matrixdotorg/mjolnir Docker tag to v1.7.0

Related to https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/3369

Ref: https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/3521

* fix synapse-admin image prefix

* fix typo

add missing prefix to synapse-admin version

Related to: https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/3519

* switch to synapse-admin fork

* Fix typo

* Close unclosed ) and reword sentence

---------

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

Related to:

- https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/3518
- https://github.com/hifi/heisenbridge/issues/294

With this patch, when `matrix_heisenbridge_path_prefix` is the default
one we use (`/heisenbrdige`), URLs like this are constructed:

https://matrix.DOMAIN/heisenbridge/_heisenbridge/media/SERVER_NAME/MEDIA_ID/CHECKSUM/FILENAME

If `matrix_heisenbridge_path_prefix` is set to `/`, URLs like this are constructed:

https://matrix.DOMAIN/_heisenbridge/media/SERVER_NAME/MEDIA_ID/CHECKSUM/FILENAME

Our Traefik labels support handling both cases correctly.

Add temp suffix for container name to avoid conflict

Update ajbura/cinny Docker tag to v4.2.0

Update vectorim/element-web Docker tag to v1.11.77

Update ghcr.io/etkecc/honoroit Docker tag to v0.9.26

`matrix_client_schildichat_docker_image` was adjusted to use the
Github Container Registry in 171f5f84a2cd058f0c53780, but the Renovate marker was not adjusted.

Related to: https://github.com/spantaleev/matrix-docker-ansible-deploy/pull/3485

Related to https://etke.cc/news/d3uw4utq4t3_rpxicrrfqqou_ynmptqjgk95pt-3n2s/

As reported in https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/3451#issuecomment-2331316593

Likely the solution to https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/3451

update agru url in installing.md

Fixes https://github.com/spantaleev/matrix-docker-ansible-deploy/issues/3504

update link to agru at github