Fix allowed regions handling

[Aurelien30000]

Overview

Fixes #364

Description

Manually add a region extent when performing a brush action:

• adapt block get/set to protected regions

### Submitter Checklist
- [x] Make sure you are opening from a topic branch (**/feature/fix/docs/ branch** (right side)) and not your main branch.
- [x] Ensure that the pull request title represents the desired changelog entry.
- [x] New public fields and methods are annotated with `@since TODO`.
- [x] I read and followed the [contribution guidelines](https://github.com/IntellectualSites/.github/blob/main/CONTRIBUTING.md).

[dordsor21]

fwiw this is was FAWE does for //copy https://github.com/IntellectualSites/FastAsyncWorldEdit/blob/main/worldedit-core/src/main/java/com/sk89q/worldedit/command/ClipboardCommands.java#L286