refactor(team-colors): collapse disagreeing team palettes into one source of truth

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.

Game/scripts/HUDController.gd

@@ -24,10 +24,6 @@ class_name HUDController
 @onready var thrust_bar: HudGauge = get_node_or_null("Control/Instruments/Cluster/ThrustBar")
 @onready var camera_mode_label = get_node_or_null("Control/Instruments/Cluster/CameraModeLabel")
 
-# Team identity, mirroring TEAM_COLORS in ship.gd
-const TEAM_NAMES := {0: "Blue", 1: "Orange"}
-const TEAM_COLORS := {0: Color(0.25, 0.55, 1.0), 1: Color(1.0, 0.5, 0.15)}
-
 var ship: Node
 var _last_score := {0: 0, 1: 0}
 
@@ -66,6 +62,20 @@ func _initialize_hud():
 	if timer_label and is_instance_valid(timer_label):
 		timer_label.visible = has_timer
 
+	# Team identity (name + color) is fixed regardless of whether this
+	# mode tracks score, so set it here rather than baking it into the
+	# scene where it can't track TeamColors.
+	if team0_name_label and is_instance_valid(team0_name_label):
+		team0_name_label.text = TeamColors.TEAM_NAMES[0]
+		team0_name_label.add_theme_color_override("font_color", TeamColors.TEAM_COLORS[0])
+	if team0_score_label and is_instance_valid(team0_score_label):
+		team0_score_label.add_theme_color_override("font_color", TeamColors.TEAM_COLORS[0])
+	if team1_score_label and is_instance_valid(team1_score_label):
+		team1_score_label.add_theme_color_override("font_color", TeamColors.TEAM_COLORS[1])
+	if team1_name_label and is_instance_valid(team1_name_label):
+		team1_name_label.text = TeamColors.TEAM_NAMES[1]
+		team1_name_label.add_theme_color_override("font_color", TeamColors.TEAM_COLORS[1])
+
 	# Score display follows the same pattern: modes without scoring
 	# (e.g. free play) just don't show it
 	var has_score = game_manager and game_manager.has_signal("score_changed")
@@ -177,9 +187,9 @@ func _on_match_ended(winning_team: int, score: Dictionary):
 		result_label.remove_theme_color_override("font_color")
 		_set_result_panel_accent(Color(1, 1, 1, 0.2))
 	else:
-		result_label.text = "%s team wins!" % TEAM_NAMES[winning_team]
-		result_label.add_theme_color_override("font_color", TEAM_COLORS[winning_team])
-		_set_result_panel_accent(TEAM_COLORS[winning_team])
+		result_label.text = "%s team wins!" % TeamColors.TEAM_NAMES[winning_team]
+		result_label.add_theme_color_override("font_color", TeamColors.TEAM_COLORS[winning_team])
+		_set_result_panel_accent(TeamColors.TEAM_COLORS[winning_team])
 	final_score_label.text = "%d - %d" % [score.get(0, 0), score.get(1, 0)]
 	result_overlay.visible = true
 	_animate_result_panel_in()

Game/scripts/arena_boundary.gd

@@ -91,8 +91,8 @@ const DECK_SHADER_PATH := "res://shaders/arena_deck.gdshader"
 
 @export var field_tint := Color(0.45, 0.65, 1.0)
 @export var field_intensity := 0.09
-@export var team0_tint := Color(0.15, 0.45, 1.0)
-@export var team1_tint := Color(1.0, 0.35, 0.25)
+@export var team0_tint := TeamColors.TEAM_COLORS[0]
+@export var team1_tint := TeamColors.TEAM_COLORS[1]
 
 # The single merged surface shell and the material whose camera-side fade
 # _process() drives. Both stay null in headless runs, which never render.

Game/scripts/goal.gd

@@ -10,9 +10,6 @@ extends Area3D
 
 signal goal_scored(team: int)
 
-# Frame tints, indexed by team.
-const TEAM_COLORS := [Color(0.2, 0.55, 1.0), Color(1.0, 0.4, 0.28)]
-
 # The pocket is sunk into the end wall, so it can be at most as deep as that
 # wall is thick or it pokes out the back of the arena. ArenaBoundary cuts the
 # matching aperture in the hull (see its GOAL_APERTURE_* constants).
@@ -52,7 +49,7 @@ func _on_body_entered(body):
 func _build_visuals() -> void:
 	var mouth := ($CollisionShape3D.shape as BoxShape3D).size
 	var half := Vector2(mouth.x, mouth.y) / 2.0
-	var tint: Color = TEAM_COLORS[team % TEAM_COLORS.size()]
+	var tint: Color = TeamColors.TEAM_COLORS[team % TeamColors.TEAM_COLORS.size()]
 
 	# One ArrayMesh, four surfaces (pocket, net, bezel, rim). They stay separate
 	# surfaces rather than sharing materials because they aren't visually

Game/scripts/ship.gd

@@ -25,13 +25,6 @@ extends RigidBody3D
 @export var ceiling_pull_strength = 11.5 # Ceiling grav-plating strength; nets above gravity so a ship can hold a ceiling
 @export var ceiling_pull_range = 3.0     # Metres from the ceiling where pull begins
 
-# Accent colours per team, applied to the nose and tail fin meshes so the
-# two sides are tellable apart at a glance.
-const TEAM_COLORS := {
-	0: Color(0.25, 0.55, 1.0),
-	1: Color(1.0, 0.5, 0.15),
-}
-
 # Non-tinted hull meshes, runtime-merged into one ArrayMesh by
 # _build_merged_hull() (Nose/TailFin stay separate MeshInstance3Ds since
 # _apply_team_color() retints them per-team and must keep addressing them by
@@ -73,7 +66,7 @@ static var _team_materials: Dictionary = {}  # team:int -> StandardMaterial3D
 static func _get_team_material(team: int) -> StandardMaterial3D:
 	if _team_materials.has(team):
 		return _team_materials[team]
-	var color: Color = TEAM_COLORS.get(team, TEAM_COLORS[0])
+	var color: Color = TeamColors.TEAM_COLORS.get(team, TeamColors.TEAM_COLORS[0])
 	var accent := StandardMaterial3D.new()
 	accent.albedo_color = color
 	accent.metallic = 0.3

Game/scripts/team_colors.gd

@@ -0,0 +1,10 @@
+class_name TeamColors
+
+# Single source of truth for team identity. Ship nose/tailfin, HUD result
+# panel, goal rim/net, and the arena end-zone floor shader all read from
+# here — do not restate these values locally (see TODO.md history).
+const TEAM_NAMES := {0: "Purple", 1: "Green"}
+const TEAM_COLORS := {
+	0: Color(0.48, 0.18, 0.88),
+	1: Color(0.24, 0.86, 0.42),
+}

Game/scripts/team_colors.gd.uid

@@ -0,0 +1 @@
+uid://c6r8q1dpd8klq