The configuration doesn't have `group`, so it's a slightly different
configuration to the rest of the *arr services.
I also want to move the other two indexer modules under `servarr`, as
they are all closely related.
I renamed the option and refactored how it worked to make it more
explicit that it enables the entire suite by default, with explicit
opt-out of individual components (or fine-grained opt-in as an
alternative).
