We inherited the disabled-by-default setting from conduit. Conduwuit
change it to enabled-by-default in [1]. This can make things confusing
for users migrating from conduwuit to grapevine, especially since we
currently do not log a warning when federation is disabled.
[1]: 24605e151d
This change is fully automated, except the `rustfmt.toml` changes and
a few clippy directives to allow specific functions with too many lines
because they are longer now.
This makes it possible to deploy Grapevine while using a database
originally created by Conduit, including leaving the admin bot user's
localpart the same as before.
