A new intermediate mob with a power level between Chillagers and Frostologers. Specializes in melee frost combat. A somewhat experimental feature so I may update the issue as time goes on.

Checklist:

• Add a Harrow mob (use the Vindicator as placeholder for model)
• Have one spawn in a Chillager Outpost
• Allow them to spawn in Frostologer Castles
• Add texture
• Add a custom model with an arm that was replaced an icicle, sort of like a pirate hook
• Give it a hook attack that pulls enemies towards itself with a high reach, and slows them

gonna delay this mob to 2.1, the stray can fill in as a third mob for the castle temporarily