chore: move gRPC client module root up

[zepatrik]

Related issue

closes #606

Proposed changes

Move go.mod and package.json up to the proto root. This way the whole path is included in the distributed package.
Also for the js client, there is now an index file in the version directory that accumulates all exports, and also an index file in the package root that points to the latest version.

Further comments

It would be nice to automate stuff around the index.js files.

TODO:

• adjust release automation

[aeneasr]

Please document this as a breaking change in the git commit message. Best would be to show how to migrate from the old grpc module to the new one!

[zepatrik]

So I put this as a commit message?

---

BREAKING: The npm package @ory/keto-grpc-client from now on includes all API versions. Because of that, the import paths changed. For migrating to the new client package, change the import path according to the following example:

- import acl from '@ory/keto-grpc-client/acl_pb.js'
+ // from the latest version
+ import { acl } from '@ory/keto-grpc-client'
+ // or a specific one
+ import acl from '@ory/keto-grpc-client/ory/keto/acl/v1alpha1/acl_pb.js'

[aeneasr]

Yup! :)