Add Dockerfile for Render deployment

Author: magnus-lower

Docker

@@ -0,0 +1,13 @@
+# Use official Maven image to build the app
+FROM maven:3.9.6-eclipse-temurin-17 AS build
+WORKDIR /app
+COPY . .
+RUN mvn clean package -DskipTests
+
+# Use a lightweight JDK base image to run the app
+FROM eclipse-temurin:17-jdk-jammy
+WORKDIR /app
+COPY --from=build /app/target/*.jar app.jar
+EXPOSE 8080
+ENV PORT=8080
+ENTRYPOINT ["java", "-jar", "app.jar"]