Add insomniafix app with fixes for phantoms

[federicocarboni]

A while back I wrote a script to make phantoms less annoying and I think it could be useful to other.

As of now the app contains the following bug fixes and changes for phantoms spawning:

• Phantoms no longer spawn for creative mode players (fixes MC-145177).
• Phantoms no longer spawn when the mobcap is saturated.
• Phantoms no longer spawn on mushroom islands and the void (fixes MC-126778 and MC-127599).
• Optionally fix MC-154372 reverting phantom damage to 6 hearts instead of 2.
• Optionally enable large phantom spawning which increases the size of phantoms the longer you go without sleeping. Similar to VanillaTweaks' large phantoms datapack.

All these can be configured individually with the /insomniafix command.

The app works by disabling phantom spawning and reimplementing it from scratch in Scarpet. I tested it and there should be no major changes in spawning rates even when respecting the mobcap.