[announce] Follow ups posts on Mastodon should be marked as unlistet

[McPringle]

Is your feature request related to a problem? Please describe.
Using threaded status on Mastodon, all posts are public. So all posts show up on all timelines equally.

Describe the solution you'd like
The first post should be public. All following posts (threaded answers) should be posted as "unlisted". This will result in a "real thread". That is the recommended behavior of many instances.

• Post 1 (public) -> visible in all timelines
  • Post 2 (unlisted) -> visible when opening Post 1
  • Post 3 (unlisted) -> visible when opening Post 1

[aalmiray]

See visibility property that may be set as part of the data payload https://docs.joinmastodon.org/methods/statuses/

[aalmiray]

Matter of fact, we could set the visibility field automatically as unlisted when creating a new Status object with whose replyToId is non null. IOW there's no need to expose a user facing configurable setting for this property at the moment.

[aalmiray]

Released in v1.4.0 -> https://github.com/jreleaser/jreleaser/releases/tag/v1.4.0