* feat(folia): added folia support

* chore(folia): apply folia-supported: true label

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Co-authored-by: R00tB33rMan <rootb33rman@gmail.com>

* Fix warnings about task not being cacheable
* Add plugin to install Spigot
* Explicitly cache BuildTools products
* Move reobfuscation to a plugin
* Update compilation instructions

* Hack around SpecialSource limitations with ProGuard mappings
* Relocate PlanarWrappers
* Use libs for shadow exclusion

I don't think SpecialSource is likely to make major changes to JarMapping, but RemapperProcessor hasn't been changed in 4 years.
This is less efficient in terms of lookup speed, but does not require the hacky JarMapping extension and doesn't require a second copy of the field mappings to be kept in memory.

This technically allows edge cases where the package (or class, for classes with no package) can start with L and be incorrectly matched, but that feels like a case of play stupid games, win stupid prizes. Classes should be packaged, and package names should be lower case.
Requires a much less hacky change to JarMapping to optimize.

In my defense, reading is really hard

and publishing it, but we don't talk about that

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