Update web-ui to follow Drift patterns

- Refactor juce-bridge.ts to use event-based SliderState/ToggleState classes
- Update hooks to use proper event listeners instead of polling
- Enhance ActivationScreen with CRT-themed UI and proper error handling
- Update OxideVisualizer with pixelated city scene and CRT post-processing
- Add scanlines, chromatic aberration, wobble, and vignette effects

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: nlaroche