Generate Haskell->JS->GRPC bindings automatically

Currently, `cardano-wasm`'s `grpc` module calls the automatically generated gRPC or gRPC-web JavaScript bindings. But when those bindings change, the calls from Haskell to the GRPC JS bindings may break, and that break will happen at runtime.

The goals are:
- To be able to maintain the RPC module of the `cardano-wasm` library exclusively from Haskell.
- For changes to the RPC interface (`cardano-rpc`) to only affect Haskell (and not JS).

Because:
- JS breaks silently.
- But Haskell breaks at compile time (this is better for maintenance and reliability).