Look into Source Generators as future improvements

[jsturtevant]

Instead of generating code via a command we could have code generated on demand via Source Generators. This could allow to pick up the wit file and automatically add all bindings. Things like attributes could provide additional meta data around naming as is done in https://github.com/Yeseh/wasm-sourcegen.

The cli tool could still be useful for initialization and building but we could also provide build targets that do the additional building as an alternative.

Also at some point in the future, c bindings won't be necessary either:

• because they will be generated automatically C#-only way to declare wasm imports and exports SteveSandersonMS/dotnet-wasi-sdk#30
• or AOT LLVM compiling will land https://github.com/dotnet/runtimelab/blob/feature/NativeAOT-LLVM/docs/using-nativeaot/compiling.md#webassembly-native-libraries