feat: scaffold relay client auth workspace

Dockerfile.auth-api

@@ -0,0 +1,12 @@
+FROM rust:1.86 as build
+WORKDIR /app
+COPY . .
+RUN cargo build --release -p auth-api
+
+FROM debian:bookworm-slim
+RUN useradd -r -u 10001 appuser
+WORKDIR /app
+COPY --from=build /app/target/release/auth-api /usr/local/bin/auth-api
+USER appuser
+EXPOSE 8080
+CMD ["auth-api"]