Wendigo Spawn Egg

Implement only these approved requirements: - Create a hostile Wendigo entity using the fixed biped model, with a generated spawn egg. Apply the supported default dimensions, health, attack damage, armor, tracking range, sound family, hostile default goals, and no natural spawning unless separately specified. - Create the wendigo texture: A frightening gaunt wendigo monster with elongated limbs, antlers, dark fur, glowing pale eyes, and a horror-themed bipedal silhouette. - Create the wendigo_spawn_egg texture: A Minecraft-style spawn egg patterned in dark brown, charcoal, bone white, and faint glowing pale green to represent a wendigo.