🐛 fix arena box being invisible when looking straight down

- adding this `height` field makes it not cull when looking straight down during the red intro cutscene

datapacks/omegaflowey/data/omegaflowey.entity/function/directorial/boss_fight/shared/arena_box/initialize.mcfunction

@@ -8,3 +8,6 @@ tag @s add arena_box
 # Store boss fight UUID to storage for later use
 function gu:generate
 data modify storage omegaflowey:bossfight arena_box_uuid set from storage gu:main out
+
+execute on passengers if entity @s[tag=aj.omegaflowey_arena_box.bone] run \
+  data merge entity @s { height: -10.0f }