HUDController found its ship via get_first_node_in_group("ship"), a group
that has 2+ members once a match has an AI opponent — it only worked
because the player ship happened to spawn first. spawn_camera_rig now
wires the HUD's ship the same way it already wires the camera rig's
target.
ship.gd, HUDController.gd, and goal.gd each declared their own TEAM_COLORS,
arena_boundary.gd/arena_deck.gdshader had a third pair, and HUD.tscn baked
in a fourth (hardcoded "BLUE"/"ORANGE" labels) — nose, goal rim, end zone,
and scoreboard all rendered different blues. New scripts/team_colors.gd
(class_name TeamColors) is now the single source every one of those reads
from, and team identity moves to purple/green.