Add Procreate Brush and Brush Set file Types

[jeffreybaird]

Description

This PR introduces new MIME types for Procreate-specific file formats:

• application/vnd.procreate.brush for .brush files
• application/vnd.procreate.brushset for .brushset files

These MIME types correspond to Procreate’s custom brush and brush set formats, commonly used shared by artists and designers on the Procreate app.

Details

• application/vnd.procreate.brush

  • Extensions: .brush
  • Description: Procreate Brush
  • Sources: Procreate Handbook - Brush Sharing

• application/vnd.procreate.brushset

  • Extensions: .brushset
  • Description: Procreate Brush Set
  • Sources: Procreate Handbook - Brush Sharing

Notes:

The brushset file type is a collection of Brush files