[Help wanted] And various language bindings for VAD

[csukuangfj]

https://github.com/k2-fsa/sherpa-ncnn/pull/353 adds support for VAD.

However, it only adds the C++ API.

Help from the community is appreciated to support the following languages

• [ ] C
• [ ] Python
• [ ] Kotlin
• [ ] Go
• [ ] C#
• [ ] JavaScript
• [ ] Swift

We also need to add VAD + microphone examples

Note that all of the above can follow what we have done in sherpa-onnx

The major change is to replace onnx with ncnn. The remaining code can be copied literally from sherpa-onnx.