The size of the audio buffer was incorrectly doubled when creating the
script processor.
latencyHint is expressed in seconds, not milliseconds.
Additionally, on some browsers it actually affect the performance and
stability of the audio driver.
For this reason it has been completely disabled (interactive) and a not
has been left for future reference.

The API is implemented in javascript, and generates C functions that can
be called from godot.
This allows much cleaner code replacing all `EM_ASM` calls in our C++
code with plain C function calls.
This also gets rid of few hacks and comes with few optimizations (e.g.
custom cursor shapes should be much faster now).

Rewrote AudioDriverJavaScript to support multiple processor nodes.
The old (and deprecated) ScriptProcessorNode when threads are not
available, and the new AudioWorklet API when threads are enabled.

The new implementation uses two ring buffers and a shared state to
communicated with the AudioWorklet thread.

The audio.worklet.js JavaScript file is always added to the export
template, but only really used (and download) in the thread build.