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>

.gitignore

@@ -0,0 +1,15 @@
+# Godot's import/cache folder. Regenerated on open, and it also holds
+# .godot/export_credentials.cfg, which must never be published.
+.godot/
+
+# Build outputs and the generated Android build template (~325 MB combined).
+# All reproducible: the template comes from Godot's "Install Android Build
+# Template", the rest from an export.
+builds/
+android/build/
+*.apk
+*.aab
+*.idsig
+
+# Android's "don't index this as media" marker, not project content.
+.nomedia