v0.12.5

• Bunny setup attaches an existing app. dstack deploy setup wrote
  .dstack/deploy.json only when every step succeeded, so a setup that
  stopped halfway left an app behind, and the next setup created another.
  Setup now attaches the app with the project's name, or the one you pick
  in a terminal or pass with --app <name or id>; --app new creates a
  new one.

• Bunny setup handles a domain that is already registered. When the
  domain was still on the pull zone of an earlier app, Bunny answered
  "The hostname is already registered" after setup had created the new
  app. dstack deploy setup --provider bunny now checks the domain before
  it creates anything and offers to move it to the new app; without a
  terminal, it stops and says which pull zone has it.