[FEAT] Pls add "transparent" to the available colors

[Nxaj]

Is your feature request related to a problem? Please describe.

"Paint Transparent" only pains black instead of the real transparent
This would really help to protect Artworks against griefers :)
Thank you for this Bot!

Describe the solution you'd like

"transparent" as a available color

Describe alternatives you've considered

No response

Additional context

No response