Pedro Tacla Yamada

There are some glitches on the multi track looper processors on iOS. Likely due to input/output channel mismatch

* Rust and dart threads should stop work after quit has started

Implement a gate, which can notify other processors of when a signal shifts between a certain threshold.

`crates/augmented/audio/audiounit` is successfully hosting views ; now it needs to render audio

https://github.com/yamadapc/augmented-audio/runs/3156489201?check_suite_focus=true

I believe there's a memory leak around windows not being cleaned-up

* Audio processor options are built based on CLI input & the default audio thread options * If the user uses a non-default host/device, the stream options will be different...

Implement offline render functionality into the test host.