[core] Implement mobs with bind attacking nearby players

[WinterSolstice8]

I affirm:

• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

Implements the mob AI functionality where mobs will face towards their closest target when bound an attack them (assuming they are on the enmity list of the mob) as long as their primary target with the most enmity is too far away.

Closes #5541

Steps to test these changes

Bind mob, get a lot of hate on it, move away from it, have another player stand near the mob, note it's not attacking that player, cure a player on the hate list, now the mob is will attack the player near the mob

[ampitere]

This is really cool, also works with pets.

[WinterSolstice8]

This is really cool, also works with pets.

Hmm... not sure it's supposed to... aside from BST charmed pets, and a hard maybe for jugs...

[ampitere]

This is really cool, also works with pets.

Hmm... not sure it's supposed to... aside from BST charmed pets, and a hard maybe for jugs...

I was using a SMN avatar if that helps.

[WinterSolstice8]

Yeah I don't think it's supposed to do that. I dont have any confirmation except on normal mobs