YetAnotherConfigLib 3.0 Beta 1 (for 1.19.4)

This release is parity with 3.0.0-beta.6 for 1.20.

Unfortunately, 3.0 will only be available for 1.19.4 and up, not 1.19.2. This is because YACL
now highly depends on .4's new tab system (found in the create new world screen).

If there is a high enough demand for a backport to 1.19.2, I will consider it, but no promises!