Fix detecting addons from zip file

Also set the default to `collectOutput` where it would parse the
output of an addon.

modules/backend/src/main/scala/docspell/backend/ops/AddonValidate.scala

@@ -72,7 +72,7 @@ final class AddonValidate[F[_]: Async](
         ).cast
       )
       _ <- EitherT.cond(
-        meta.options.exists(_.isUseful),
+        meta.options.forall(_.isUseful),
         (),
         InvalidAddon(
           "Addon defines no output and no networking. It can't do anything useful."