- Replace basic swirl shader with full vortex tunnel effect:
- Radial speed lines (28 primary + 14 counter-rotating) streaking past
- Zoom pull: scene rushes into the vortex mouth
- Swirl twist intensifying with portal depth
- Chromatic aberration at peak for sci-fi feel
- Portal-colored bloom from vortex center
- Tunnel rim glow ring
- White screen flash at crossing moment
- Add progress uniform (0→1) driving bell-curve intensity via sin(progress*PI)
- Portal color tints the warp based on each portal's own color
- Navigate to portal destination URL at flash peak (progress≥0.88)
- Store destinationUrl and portalColor in portal mesh userData
- Extend WARP_DURATION from 1.5s → 2.2s for full dramatic effect
Fixes#232