whisper.wasm : update Emscripten bridge to provide text segments and token data to the JS layer

[DavidGOrtega]

While Im testing the code I have seen that full_default do not return the data, just only logs it.
To be able to retrieve them I have override the print and printErr handlers to extract the data and then apply clunky regexes.
Could not be awesome if we could gather the output instead of the error code? Or both?

[ggerganov]

The C++/JS bridge in emscripten.cpp has to be extended to provide the output to the JS layer.
It's not very difficult to achieve, but I keep postponing it since it is low priority. I think it should be an easy task for people looking to contribute to the project

[DavidGOrtega]

worth a good first issue?

[DavidGOrtega]

@ggerganov I can take it

[laurensV]

This would be a great feature to have..