MM color box at code line numbers for color tags

[illyrius666]

Minecraft Dev plugin has this feature where when using named colors it shows a colored box at the code line numbers, would be cool to have that for minimessage tags too, especially with hex colors.

edit:
this would also be a nice feature to add:

we could then swap between color render and edit mode like we can do with the docs:

[Privatech38]

Since the Minecraft Dev plugin also adds support for MM color tags, we need to first check if that plugin is present and separate these gutter color pickers to:

• conflicting ones aka the ones that are also added by Minecraft Dev,
• missing ones