Add Docker build and deploy pipeline

Dockerfile

@@ -0,0 +1,18 @@
+FROM eclipse-temurin:25-jdk AS build
+WORKDIR /app
+COPY . .
+RUN sed -i 's/\r$//' gradlew \
+ && chmod +x gradlew \
+ && ./gradlew bootJar --no-daemon -x test \
+ && cp "$(ls build/libs/*.jar | grep -v plain | head -n1)" /app/app.jar
+
+FROM eclipse-temurin:25-jre
+RUN apt-get update \
+ && apt-get install -y --no-install-recommends ffmpeg \
+ && rm -rf /var/lib/apt/lists/* \
+ && useradd -r -u 1001 app
+WORKDIR /app
+COPY --from=build /app/app.jar app.jar
+USER app
+EXPOSE 8080
+ENTRYPOINT ["java", "-Xmx768m", "-jar", "app.jar"]