Initial commit: SpaceshipTest, a top-down space RTS in Godot 4.7.1

A fleet of neon-outlined ships explores a procedurally generated, seeded
infinite world: tap/joystick steering, pinch zoom, formation pivoting,
planet landings, an ore economy with extractors and haulers, and player
built structures (mothership, ship crafter, command centre).

All art is hand-drawn with draw_* calls rather than textures, and the
backgrounds are camera-relative shaders so they stay precise at large
world coordinates.

Includes a 35-test headless suite (tests/run_tests.sh) plus screenshot
tooling that renders real frames through Xvfb and Mesa softpipe, since
--headless has no GPU.

Excluded from version control: .godot/ (import cache, and it holds
export credentials), builds/, android/build/ and packaged APKs - all
regenerable, and ~325 MB combined.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

BuildingField.gd

@@ -0,0 +1,50 @@
+extends Node2D
+
+# Rebuilds every player-placed structure from GameState when the space
+# scene loads, and answers "is the fleet standing on one?".
+#
+# Buildings live in GameState rather than in the scene because Main.tscn is
+# torn down and recreated on every trip to a planet's surface - anything
+# kept only as a node would be lost on the first landing.
+
+@onready var fleet: Node2D = get_node("../Fleet")
+
+var building_scene: PackedScene = preload("res://Building.tscn")
+var spawned: Array = []
+
+
+func _ready() -> void:
+	rebuild_all()
+
+
+func rebuild_all() -> void:
+	for b in spawned:
+		if is_instance_valid(b):
+			b.queue_free()
+	spawned.clear()
+	for record in GameState.buildings:
+		_spawn(record)
+
+
+func place(type: String, at_position: Vector2) -> void:
+	GameState.add_building(type, at_position)
+	_spawn(GameState.buildings[-1])
+
+
+func get_building_fleet_is_on() -> Node2D:
+	var centre: Vector2 = fleet.get_centroid()
+	for b in spawned:
+		if is_instance_valid(b) and b.position.distance_to(centre) <= b.interact_radius:
+			return b
+	return null
+
+
+func _spawn(record: Dictionary) -> void:
+	var b: Node2D = building_scene.instantiate()
+	b.position = record.position
+	b.building_type = record.type
+	# Deferred for the same reason as the other field spawners: this can run
+	# from inside a parent's _ready() chain, where a direct add_child() is
+	# rejected while the tree is still setting up children.
+	get_parent().add_child.call_deferred(b)
+	spawned.append(b)