Realistic graphics pass: ACES tone mapping, IBL, finer ink, glass HUD

[dgexplores]

Surgical realistic-graphics pass, no layout or DOM changes. Verifies green: npm run typecheck, npm test (606 pass), npm run build, plus headless lab screenshot (lab/props.html?show=jukebox) with zero console errors.

3D (Three r186-safe):

• ACESFilmicToneMapping + exposure 1.06 in core/scene.ts, lab/stage.ts, character preview
• RoomEnvironment IBL via PMREM at environmentIntensity 0.35 so PBR (glass, cars, lids) reflects without washing toon
• Ink outline 0.0032 -> 0.0021 (preview 0.0045 -> 0.0034) for finer premium lines
• Kept PCFShadowMap: PCFSoft is deprecated since r186 and warns at runtime

2D HUD (same DOM, tokens only):

• base.css: layered soft shadows, gradient panels/buttons, blurred backdrop, focus-visible ring, Inter-first font stack with Nunito fallback
• hud.css: glass project/side panels, softer chat/hint shadows
• No modal structure changes; X/Esc behavior untouched. Size guard untouched (all files far under budget).