Chat Heads

• don't include MixinExtras on Fabric/NeoForge but require Fabric Loader 0.15+, NeoForge 20.2.84+
• fix mixin error on Forge 1.19.4+
• update MixinExtras to 0.3.1 on Forge

• port to 1.20.3
• don't include MixinExtras but require Fabric Loader 0.15

fix compatibility with Compact Chat 2.0.2

• better mod compatibility (e.g. with Clean Chat) by using MixinExtras
• support NeoForge beta

better mod compatibility (e.g. with Clean Chat) by using MixinExtras

fix server-side /say and /tell commands not showing up on client and erroring (thanks to spelunkhead!)