Fixes#11730
The v1 gRPC middleware can return native gRPC status errors such as
`codes.Unauthenticated` when the auth header is missing.
Those errors were being passed through the generic gRPC error converter,
which only handled ZITADEL errors and downgraded raw gRPC statuses to
`codes.Unknown`.
Through grpc-gateway that caused `/auth/v1/users/me` to return HTTP 500
instead of HTTP 401.
So this change preserves native gRPC status errors in
`ZITADELToGRPCError`, keeps `ExtractZITADELError` aligned with those
transport codes for activity reporting, and adds regression coverage for
the converter, middleware, and gateway HTTP behavior.
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Co-authored-by: Gayathri Vijayan <[email protected]>
