Audio realism: spatial audio capture to simulated microphone inputs

[Kinin-Code-Offical]

Goal: Unity scene audio (spatialized / surround) can be captured and fed into simulated microphones/sensors used by firmware/ROS nodes.

Scope:

• Define mic devices and sampling format/rate.
• Capture Unity mix or per-source mix, then publish frames to simulation bus.
• Deterministic option for testing.

Acceptance:

• Mic samples available to RPi guest path (via shared memory/virt device) and/or MCU ADC-style inputs.