Make Warden’s Sonic Boom Damage Editable via Attribute

Currently, the Warden’s sonic boom deals a fixed amount of damage that can’t be changed through attributes or NBT. Unlike melee attacks, there’s no way for map makers, command block users, or datapack creators to modify its power. Adding a dedicated attribute (e.g., generic.sonic_boom_damage) would give creators more control and flexibility when customizing Wardens for custom maps, challenges, or balanced gameplay tweaks.