v1.6.6 for Minecraft 1.21.4

I changed just four lines of code for it to work. I wish every version was like this.

This release brings support for Minecraft 1.21.4 with every bugfix from 1.6.4-1.6.6, notably:

Bug fixes

• Fixed some effects (especially custom ones) causing classloading errors on the dedicated server
• The camera entity no longer renders (I think that's what caused it to appear after a cutscene sometimes)
• Fixed the "Error loading float provider" spam

Compatibility

Any cutscenes made for previous versions should still work in this one. From now on, this will be the main version for development, and 1.21.1 may get some big releases once in a wihle.