Until now, if `--tags=setup-synapse` was used, bridge tasks would not
run and bridges would fail to register with the `matrix-synapse` role.
This means that Synapse's configuration would be generated with an empty
list of appservices (`app_service_config_files: []`).
.. and then bridges would fail, because Synapse would not be aware of
there being any bridges.
From now on, bridges always run their init tasks and always register
with Synapse.
For the Telegram bridge, the same applies to registering with
matrix-nginx-proxy. Previously, running `--tags=setup-nginx-proxy` would
get rid of the Telegram endpoint configuration for the same reason.
Not anymore.
The goal is to move each bridge into its own separate role.
This commit starts off the work on this with 2 bridges:
- mautrix-telegram
- mautrix-whatsapp
Each bridge's role (including these 2) is meant to:
- depend only on the matrix-base role
- integrate nicely with the matrix-synapse role (if available)
- integrate nicely with the matrix-nginx-proxy role (if available and if
required). mautrix-telegram bridge benefits from integrating with
it.
- not break if matrix-synapse or matrix-nginx-proxy are not used at all
This has been provoked by #174 (Github Issue).
