Updated Dockerfile and Woodpecker pipeline to use harbor.maximumdirect.net proxy cache for upstream images.

Dockerfile

@@ -5,7 +5,7 @@ ARG GO_VERSION=1.25
 ############################
 # Build stage
 ############################
-FROM golang:${GO_VERSION}-bookworm AS build
+FROM harbor.maximumdirect.net/proxy-dockerhub/golang:${GO_VERSION}-bookworm AS build
 
 WORKDIR /src
 
@@ -52,7 +52,7 @@ RUN --mount=type=cache,target=/root/.cache/go-build \
 ############################
 # Runtime stage
 ############################
-FROM debian:bookworm-slim AS runtime
+FROM harbor.maximumdirect.net/proxy-dockerhub/debian:bookworm-slim AS runtime
 
 # Install runtime necessities
 RUN apt-get update && apt-get install -y --no-install-recommends \