Add Sinusoidal Audio Visualizer with Toggle Support

[tailot]

This change implements a new sinusoidal audio spectrum analyzer in BeatForge. Users can now toggle between the classic bar-based visualizer and a new smooth, multi-layered sinusoidal wave by clicking anywhere on the visualization area.

Key technical improvements:

• High-rate rendering: Switched from beat-rate updates to a 60fps requestAnimationFrame loop for fluid visual feedback.
• Canvas implementation: Added an overlay canvas that uses the frequency data to modulate the amplitude and phase of sine waves.
• Robust responsiveness: Added a window resize handler to ensure the visualizer maintains correct proportions and clarity across different screen sizes.
• State management: Introduced a persistent vizMode state in the UIController to handle the coexistence and switching of visualizers.

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PR created automatically by Jules for task 4528083277700644258 started by @tailot

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