(feat) Added Web Audio library ("native" C interface).
(feat) Linked fill_buffer function (JS<->C).
(feat) Implemented C audio buffer.

The SRE does not yet function. It freezes.
It may be that the process is too intensive to be native.
Next steps:
- [ ] Move to a Web Worker (use Transferable objects for messages)
- [ ] Ensure get_pos/set_pos are being set