Extract rendering controllers, add static obstacles + skyscrapers

[holoduke]

Summary

Structural refactor of app.js (2334 → 1272 LOC, −45%) extracting three rendering controllers and a sun state owner, plus two new gameplay/scenery systems built on top of the cleaner architecture.

• Controllers: HeightmapPipeline, ShadowController, PostProcessingController, SunController — each owns its state + public API; TerrainApp holds the composition root and exposes getter/setter proxies so ControlPanel continues to work unchanged.
• Static obstacles: new StaticObstacleIndex 2D spatial hash with AABB slab sweep. CollisionDetector wires it into the laser-march (tunnel-proof) and into per-frame player-position checks. Player crash into an obstacle triggers the existing death-explosion pipeline.
• Skyscrapers: procedural window-grid shader (local-space UVs, yaw-invariant), mirrored sky reflection via reflect(-viewDir, normal) + fresnel mix, specular sun glint on glass, lit-window emission (~18%, per-building seed). setBuildingDensity(0..25) slider in ControlPanel; placement scans the real heightmap for flat sites (Δh ≤ 28 over a 180-unit footprint, 260-unit spacing) and drops the rest.

Perf / correctness fixes along the way

• Pre-allocated ~30 Vector3 in ShadowController.updateCascadeCamera (previously new Vector3 per cascade per frame).
• Pre-allocated 4 Vector3 in Player flight/camera/laser/bomb hot paths.
• Pre-allocated testPoint in CollisionDetector.
• Fixed death-explosion rAF leak — handle stored + cancelled in Player.dispose.
• Removed window.game global (18 reach-throughs) → constructor injection.
• Removed late-set inputManager.game = this back-pointer.
• Moved InputManager.toggleMenu's game.app.controlPanel.panel deep reach into Game.toggleMenu() / Game.isMenuVisible().
• Race fix: InputManager.toggleMenu now clears intentionalUnlock and cancels any pending re-lock setTimeout on rapid M-key toggling.
• PostProcessingController.setup is idempotent (calls dispose first).
• Reconciled ShadowController resolution default (4192) with its setter clamp (was 2048; now both 4096; slider range matches).
• Removed dead updateEngineGlow (mesh.traverse every frame for a flag that was never set).
• Unified AudioManager fadeIn/fadeOut behind _fadeTo() helper.
• Extracted FLIGHT_CONSTANTS (speeds, turn rates, weapon timings, camera tunables).
• Collapsed duplicated effectParameters initialisation in app.js.
• Stripped 4 hot-path console.logs from CollisionDetector's laser march.

Cleanup

• Added .gitignore for node_modules/, dist/, .DS_Store, .vite/, *.log; untracked 1375 previously-committed build files.
• Removed unused assets: 5 skybox PNGs, 3 standalone textures, JetstreamArcade.mp3, shift.glsl, src/assets/screenshots/.
• Removed dead noise/index exports, geometry.cube, orphaned HeightmapPipeline methods with no callers, toggleRenderer/showRendererNotification (only referenced from a disabled KeyG handler).
• Derived-state proxy setters on TerrainApp throw when written, to catch accidental external mutation of moved fields.

File structure

src/
├── app.js                               (1272, was 2334)
├── world/
│   ├── HeightmapPipeline.js             (new, 293)
│   ├── SunController.js                 (new, 39)
│   └── StaticObstacleIndex.js           (new, 230)
├── rendering/
│   ├── ShadowController.js              (new, 498)
│   └── PostProcessingController.js      (new, 203)
└── assets/shaders/
    └── skyscraper.{vert,frag}           (new)

Test plan

• npm run build clean (verified: 2.69s, no warnings)
• Page loads; canvas initialised; menu renders
• ENGAGE → play mode: 🎮 Game system initialized → ✅ Player loaded → 🎮 Input enabled → ✅ Game started in play mode
• Fire lasers (Space) / bombs (KeyB) without errors
• M-key toggles menu without pausing
• Shadow / Bloom / Post-FX toggles round-trip through controllers
• "Generate Ridged Terrain" exercises HeightmapPipeline end-to-end: 📋 Initialized base & master heightmap → 🏔️ Generating ridged → ✅ Rebuilt master heightmap → 🔄 Updated terrain from master
• Flying the player plane into a skyscraper/obelisk → crash → death explosion
• Laser fired at a skyscraper → collision returns kind: "obstacle"
• Building density slider 0 → 25 cleanly adds/removes buildings; obstacle-count tracking matches at each step
• Windows show mirrored sky reflection + sun glint on glass; walls pick up diffuse sun; lit windows glow warm amber

Net diff

26 source files modified/added/deleted. −577 source LOC after cleanup.