DSP-Based Drum Synthesis and Saturation

[Pitrat-wav]

This PR implements an advanced drum synthesis engine based on the provided DSP research. It replaces static triggers with dynamic, velocity-sensitive models that simulate analog behavior through micro-randomization and soft-clipping saturation.

Highlights:

• Velocity-Sensitive Synthesis: All drum models (Kick, Snare, Hi-Hat, Clap) now accept a velocity parameter that scales their internal VCAs and noise layers.
• Master Saturation: A new WaveShaper-based 'DRIVE' control has been added to the drum master bus, using a soft-clipping tanh approximation for 'analog' glue.
• Analog Drift: The sequencer now introduces subtle per-hit randomization to simulate the fluctuations of hardware components.
• Improved Routing: The Open Hi-Hat now has its own dedicated gain node, allowing for independent mix control.

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PR created automatically by Jules for task 16520162776944549987 started by @Pitrat-wav

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