Initial project setup: Rust/WASM solar system simulator with SvelteKit frontend

- Rust workspace with 4 crates: orbital-mechanics, mass-driver-core, mass-driver-wasm, mass-driver-backend
- Keplerian orbital mechanics engine with JPL elements for 14 bodies (Sun, 8 planets, Pluto, Ceres, Europa, Titan, Ganymede)
- Kepler equation solver and orbital position computation compiled to WASM
- SvelteKit frontend with Tailwind CSS, Canvas2D renderer showing animated solar system
- Orbit ellipses, planet dots with labels, Sun glow, grid, scale bar, pan/zoom controls
- Time controls (play/pause, 5 speed levels, date picker) driving live simulation
- 2D/3D view toggle (3D placeholder for Threlte integration)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,26 @@
+# Rust
+target/
+Cargo.lock
+
+# Node
+node_modules/
+frontend/node_modules/
+frontend/.svelte-kit/
+frontend/build/
+
+# WASM build output
+crates/mass-driver-wasm/pkg/
+
+# Environment
+.env
+.env.local
+
+# IDE
+.idea/
+.vscode/
+*.swp
+*.swo
+
+# OS
+.DS_Store
+Thumbs.db