fix(content): prevent npcs from tick healing non-recoil damage

[tannerdino]

• Npc's can no longer tick heal incoming damage, with the exception of ring of recoil damage. However, xp gained and kill credit should still use the capped damage.

From Video:

• Kill credit will now only update on successful hit

• Also fixes %com_maxhit should be stored in local var #1403

[mark-b5]

Heropoints and xp should still be capped to current hp

[tannerdino]

Heropoints and xp should still be capped to current hp

Good catch

[tannerdino]

Notable change I do here is I only call npc_heropoints if the hit lands. Is this true in osrs? Right now it looks like you'll be placed into the npc's hero index if you do 0 damage?