Add script to build Docker image from forked code

gmfork-build-docker.sh

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+REPO_ROOT="$(cd "$(dirname "$0")" && pwd)"
+ARTIFACTS_DIR="$REPO_ROOT/artifacts"
+
+if [ -z "${DOCKER_REGISTRY:-}" ]; then
+    echo "Error: DOCKER_REGISTRY is not set" >&2
+    exit 1
+fi
+
+# Build
+cd "$REPO_ROOT"
+./mvnw --batch-mode --no-transfer-progress install -Ph2 -DskipTests
+
+# Prepare artifacts
+rm -rf "$ARTIFACTS_DIR"
+mkdir -p "$ARTIFACTS_DIR"
+
+cp commafeed-server/target/commafeed-*-jvm.zip "$ARTIFACTS_DIR/"
+unzip -q "$ARTIFACTS_DIR"/*-jvm.zip -d "$ARTIFACTS_DIR/extracted-jvm-package"
+mv "$ARTIFACTS_DIR/extracted-jvm-package"/commafeed-* "$ARTIFACTS_DIR/extracted-jvm-package/quarkus-app"
+
+# Build image
+docker build \
+    --platform linux/amd64 \
+    --file commafeed-server/src/main/docker/Dockerfile.jvm \
+    --tag "$DOCKER_REGISTRY/commafeed-fork:latest" \
+    .
+
+rm -rf "$ARTIFACTS_DIR"
+
+echo "Built: $DOCKER_REGISTRY/commafeed-fork:latest"