Update README.md to add instructions to use with connect

[joshcarp]

Hello,
So this adds instructions to add vtprotobuf to connect.

connect-go uses the same interface as the grpc for codec and so it does work grpc.Codec{} but another alternative would be to copy the grpc directory to make a connect directory to decouple them.

Let me know what you think!

[mattrobenolt]

👋 hey @joshcarp lemme compare this with the codec I wrote. It might just be the same here and I can unify.

[mattrobenolt]

Ok, so in my experience, we've opted to use something more like this: https://github.com/planetscale/psdb/blob/main/core/codec/codec.go

The main difference being, it also supports the fallback to non vtprotobuf encoded objects. It's not always practical to assume vtprotobuf is used for every message.

@vmg what are your thoughts here?

[joshcarp]

@mattrobenolt do you want me to add that package here as a new connect package?

[vmg]

@joshcarp: No, I think it's perfectly OK if you host the package yourself and we point at it from the documentation. I'll merge this!