Status shields and reactions

Shield capacity=base+perSkillLevel*skillLevel+worldLevel*worldBonus; break occurs when accumulated damage>capacity. Damage callback clears only channels handled by HitData.ApplyModifier, so raw/nonPlayer bypass. React spawns a projectile at damage>=threshold with per-item-level damage. Crown setup/stop toggles player crown mode. Status armor adds then applies 1+multiplier per callback.