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>

tests/_ingame_buildings_preview.gd

@@ -0,0 +1,27 @@
+extends Node2D
+
+# Preview scene - NOT run by run_tests.sh (underscore prefix). Renders the
+# buildings through the REAL game path: records in GameState, spawned by
+# Main.tscn's BuildingField, drawn under the game's own camera. The sibling
+# _crafter_preview only proves Building.gd's art in isolation; this proves
+# what actually reaches the screen in a running game.
+#
+#   bash tests/screenshot.sh res://tests/_ingame_buildings_preview.tscn /tmp/out.png 40
+
+
+func _ready() -> void:
+	GameState.buildings.clear()
+	GameState.extractors.clear()
+	GameState.reset_formation()
+	GameState.add_building(GameState.BUILDING_MOTHERSHIP, Vector2(-230.0, 0.0))
+	GameState.add_building(GameState.BUILDING_SHIP_CRAFTER, Vector2(240.0, 0.0))
+
+	var main: Node = load("res://Main.tscn").instantiate()
+	add_child(main)
+	main.get_node("AsteroidField").set_process(false)
+	main.get_node("EnemySpawner").set_process(false)
+	# Park the fleet below the pair so the camera frames both, and zoom out
+	# far enough to see them whole.
+	main.get_node("Fleet").move_to(Vector2(0.0, 210.0))
+	var cam: Camera2D = main.get_node("Camera2D")
+	cam.zoom = Vector2(1.35, 1.35)