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>

ui_theme.tres

@@ -0,0 +1,15 @@
+[gd_resource type="Theme" format=3]
+
+; Project-wide default font size for every Control.
+;
+; This exists because the `gui/theme/default_font_size` project setting does
+; NOT reach the default theme in this build - labels without an explicit
+; override resolve to the engine fallback of 16 no matter what that setting
+; says, which is why earlier attempts to enlarge the UI text did nothing.
+; A custom Theme assigned to `gui/theme/custom` does apply.
+;
+; Individual labels that cannot fit their own text at this size carry a
+; smaller theme_override_font_sizes/font_size in the scene.
+
+[resource]
+default_font_size = 78