Documentation of Unsupported Events/APIs and Async Enhancements

[SergioK29]

Is your feature request related to a problem?
Developers need clarity on which events/APIs are unsupported in Folia and suggestions for more robust async API capabilities.

Describe the solution you'd like:
A full list of unsupported events/apis would be nice

Also more api for async stuff maybe like instead of:

for (World world : Bukkit.getWorlds()){
 for(Chunk chunk : world.getChunks()){
   // ran on main thread
 }
}

could be like this:

Folia.runOnEachRegion(tickRegion -> {
 tickRegion.getOwnedChunks().forEach(chunk -> {
  // ran on the different tick threads
 });
});