Based on our conversation in the planning meeting, we are going to have a new special page that follows from Special:Block to allow blocking in Checkuser.
- Implement the Limited form proposed by @Tchanders in T249871#6064612
- Amend the form to allow blocking multiple users in one go using the MultiSelectWidget
- The options checked/filled will apply to all users being blocked.
- Allow reblocking users per T249562: Checkuser should allow reblocking users and tag pages even if users are already blocked