directly support grpc-web

it would be great to support grpc-web with an in-process proxy instead of using a real proxy in between the frontend and the backend to translate grpc-web->proxy->grpc-server.
direct communication support instead would be a great feature

No files, tests, or entry points are named. Start by locating the project's gRPC transport and proxy-related integration points, then determine the scope and compatibility requirements for direct grpc-web communication. Done should mean a documented, tested path from a frontend to the backend without an external translation proxy.

Written by the indexing model from the issue text.