[feature] Audio support

[syoyo]

Describe the issue

glTF format is getting common file format for NTF and Metaverse usecase.
For such usecases, embedding audio data in 3D data is important but glTF 2.0 spec itself does not support audio feature.

Audio feature is supported by extensions.

KhronosGroup/glTF#1582

It'd be nice to implement basic features to handle audio data(e.g. decoding mp3, compute spatial audio settings) in TinyGLTF.

To Reproduce

N/A

Expected behaviour

TinyGLTF uses can easily play/interact audio data without additional C++ coding.

Screenshots

N/A

Additional context

N/A

[syoyo]

KHR_audio has been proposed. KhronosGroup/glTF#2137

[syoyo]

Initial parsing support was done: #429

TODO.

• Support loading audio data(mp3, flac, wav) using dr_libs https://github.com/mackron/dr_libs