feat: add Dockerfile and .dockerignore for containerized builds

.dockerignore

@@ -0,0 +1,10 @@
+.git
+.github
+target/
+*.md
+.gitignore
+.idea/
+*.iml
+.vscode/
+.DS_Store
+docker-compose*.yml

Dockerfile

@@ -0,0 +1,37 @@
+# Stage 1 - Build
+FROM eclipse-temurin:21-jdk-alpine AS build
+
+WORKDIR /app
+
+COPY mvnw .
+COPY .mvn .mvn
+COPY pom.xml .
+
+RUN chmod +x mvnw && ./mvnw dependency:go-offline -B
+
+COPY src src
+
+RUN ./mvnw clean package -DskipTests -B
+
+# Stage 2 - Runtime
+FROM eclipse-temurin:21-jre-alpine AS runtime
+
+LABEL maintainer="felipementel" \
+      description="CRUD de usuarios em Spring Boot com Ports and Adapters"
+
+RUN addgroup -S appgroup && adduser -S appuser -G appgroup
+
+WORKDIR /app
+
+COPY --from=build /app/target/*.jar app.jar
+
+RUN chown appuser:appgroup app.jar
+
+USER appuser
+
+EXPOSE 8080
+
+HEALTHCHECK --interval=30s --timeout=5s --start-period=30s --retries=3 \
+  CMD wget --no-verbose --tries=1 --spider http://localhost:8080/health/ready || exit 1
+
+ENTRYPOINT ["java", "-jar", "app.jar"]