Is your feature request related to a problem? Please describe.
Manually writing complex biome/item names is boring, a tab completion system would help users with basic operations.

Describe the solution you'd like
Add a tab completion handler to some brush params.

Describe alternatives you've considered
Add a method to brush interface to handle completion params, like commands.
Should simply return an empty list by default.

Additional context
Can be assigned to me, thanks ;)

Not using (modern) command frameworks are the source of all evil.

Right 😅 but atm I won't dig into such frameworks I have never used