Guard Villagers (Fabric) Fork

Fixes hat rotation on guard villagers. Hats were centered to body rotation instead of head rotation/angle/etc.

Known Issues:

• [NEW] GUI is missing model when interacting with a Guard Villager (fix planned for 1.21.5).
• Bow guards that have an active target have a tendency to take paths that incur fall damage when no other path is available.
• Melee guards with shields can get stuck in a permanent blocking-only loop when 1v1 against a ranged mob.