This commit adds copyright attributions in SPDX to the files for matrix-client-hydrogen following REUSE's specification.

Signed-off-by: Suguru Hirahara <acioustick@noreply.codeberg.org>

Most of these files were defining a service, usually toward the end.
These lines have been moved upward.

Some components (mautrix-signal, mautrix-gmessages, etc.) were defining
a service conditionally (only if metrics are exposed, etc). This was
causing issues like these in the Traefik logs:

> level=error msg="service \"matrix-mautrix-twitter\" error: port is missing" providerName=docker container=matrix-mautrix-twitter-..

Previously, it had to go through matrix-nginx-proxy.
It's exposed to Traefik directly via container labels now

Serving at a path other than `/` doesn't work well yet.