feat: add interactive 3D WebGL forge visualization using Three.js (Closes #865) [fj4WqyCCw3C5ShR1RfB7MoBPTpkRrBFYP1uT35g3MvT]

[waterWang]

Summary

Implements Bounty #865 (T3, 850K FNDRY) — Interactive 3D WebGL forge visualization for the homepage.

Changes

• New ForgeScene component — Three.js-powered 3D scene rendered as an interactive background on the homepage
• 3D Forge Core — Emissive anvil/forge with pulsing glow ring and inner light
• Floating Bounty Items — 6 glowing cubes representing bounties being forged, floating and rotating with gentle animation
• Particle System — 150 ember particles drifting upward with color gradients (orange to white)
• Shooting Sparks — 40 spark particles that shoot upward from the forge and fall with gravity
• Dynamic Lighting — Pulsing point light creates a breathing forge effect
• Gentle Camera Orbit — Auto-orbiting camera provides a cinematic 3D view
• 60fps Performance — Optimized with requestAnimationFrame, powerPreference: high-performance, and proper cleanup on unmount

Technical Details

• Uses vanilla Three.js (no React Three Fiber wrapper) for direct WebGL control
• Fully responsive — resizes to container dimensions
• CSS pointer-events: none ensures the scene does not interfere with page interactions
• Properly disposed on unmount (no memory leaks)

Acceptance Criteria

• 3D WebGL scene using Three.js
• Real-time bounty creation visualization (bounty cubes being forged)
• Particle effects and smooth 60fps animations
• Integrated into homepage as background

Wallet: fj4WqyCCw3C5ShR1RfB7MoBPTpkRrBFYP1uT35g3MvT (Solana - FNDRY)