Refactor: first iteration of modular and dockerized approach

Dockerfile

@@ -0,0 +1,51 @@
+# syntax=docker/dockerfile:1
+
+FROM eclipse-temurin:21-jdk-jammy AS deps
+WORKDIR /build
+COPY --chmod=0755 mvnw mvnw
+COPY .mvn .mvn
+COPY pom.xml .
+RUN --mount=type=cache,target=/root/.m2 ./mvnw dependency:go-offline -DskipTests
+
+# Compile and package the application
+FROM deps AS package
+WORKDIR /build
+ARG CACHEBUST
+COPY src src
+RUN --mount=type=cache,target=/root/.m2 ./mvnw package -DskipTests && \
+    mv target/$(./mvnw help:evaluate -Dexpression=project.artifactId -q -DforceStdout)-\
+$(./mvnw help:evaluate -Dexpression=project.version -q -DforceStdout).jar target/app.jar
+
+# Extract layers from the packaged jar
+FROM package AS extract
+WORKDIR /build
+RUN java -Djarmode=layertools -jar target/app.jar extract --destination target/extracted
+
+# DEVELOPMENT: Use the JDK and enable remote debugging.
+FROM extract AS development
+WORKDIR /build
+RUN cp -r /build/target/extracted/dependencies/ ./
+RUN cp -r /build/target/extracted/spring-boot-loader/ ./
+RUN cp -r /build/target/extracted/snapshot-dependencies/ ./
+RUN cp -r /build/target/extracted/application/ ./
+ENV JAVA_TOOL_OPTIONS -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=*:8000
+CMD ["java", "-Dspring.profiles.active=default", "org.springframework.boot.loader.launch.JarLauncher"]
+
+# PRODUCTION: Use the JRE and a non-root user.
+FROM eclipse-temurin:21-jre-jammy AS production
+ARG UID=10001
+RUN adduser \
+    --disabled-password \
+    --gecos "" \
+    --home "/nonexistent" \
+    --shell "/sbin/nologin" \
+    --no-create-home \
+    --uid "${UID}" \
+    appuser
+USER appuser
+COPY --from=extract /build/target/extracted/dependencies/ ./
+COPY --from=extract /build/target/extracted/spring-boot-loader/ ./
+COPY --from=extract /build/target/extracted/snapshot-dependencies/ ./
+COPY --from=extract /build/target/extracted/application/ ./
+
+ENTRYPOINT ["java", "org.springframework.boot.loader.launch.JarLauncher"]