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/test_build_menu_icons.gd

@@ -0,0 +1,64 @@
+extends SceneTree
+
+# Headless gameplay test: run with
+#   godot --headless -s res://tests/test_build_menu_icons.gd
+# The build menu is where a structure is chosen, so each option has to look
+# like the thing it builds. It used to pick from the generic icon set: the
+# mothership and the command centre both drew a folded MAP glyph, the ship
+# crafter drew a bare triangle and the extractor drew the same "+" as the
+# button that opens the menu - so redrawing the placed buildings changed
+# nothing about how they looked at the point of choosing one.
+#
+# Verifies, for every option in the menu:
+#   1. it uses its own dedicated building glyph
+#   2. no two options share an icon
+#   3. `icon` is a real Icon value that _draw actually handles
+
+var scene: Node
+
+const EXPECTED: Dictionary = {
+	"MothershipButton": IconButton.Icon.MOTHERSHIP,
+	"CrafterButton": IconButton.Icon.CRAFTER,
+	"CommandButton": IconButton.Icon.COMMAND_CENTER,
+	"ExtractorButton": IconButton.Icon.EXTRACTOR,
+}
+
+
+func _initialize() -> void:
+	scene = load("res://Main.tscn").instantiate()
+	root.add_child(scene)
+
+
+func _process(_delta: float) -> bool:
+	var menu: Node = scene.get_node("UI/BuildMenu")
+	var seen: Array = []
+	var ok: bool = true
+
+	for name in EXPECTED:
+		var button: IconButton = menu.get_node_or_null(name)
+		if button == null:
+			print("%s: MISSING" % name)
+			ok = false
+			continue
+		var expected: int = EXPECTED[name]
+		var matches: bool = button.icon == expected
+		# An out-of-range int would silently draw an empty frame, since
+		# _draw's match simply falls through.
+		var in_range: bool = button.icon >= 0 and button.icon < IconButton.Icon.size()
+		print("%s: icon=%d expected=%d ok=%s in_range=%s" % [
+			name, button.icon, expected, matches, in_range
+		])
+		if not (matches and in_range):
+			ok = false
+		if button.icon in seen:
+			print("%s: icon %d is already used by another option" % [name, button.icon])
+			ok = false
+		seen.append(button.icon)
+
+	if ok:
+		print("TEST_BUILD_MENU_ICONS: PASS")
+		quit(0)
+	else:
+		print("TEST_BUILD_MENU_ICONS: FAIL (build options are not using their own building glyphs)")
+		quit(1)
+	return true