feat: Integrate OpenTelemetry for distributed tracing in both frontend and backend applications.

backend/Dockerfile

@@ -4,6 +4,7 @@ COPY pom.xml .
 RUN mvn dependency:go-offline -B
 COPY src ./src
 RUN mvn package -DskipTests -B
+RUN curl -L -o opentelemetry-javaagent.jar https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/latest/download/opentelemetry-javaagent.jar
 
 FROM eclipse-temurin:17-jre-alpine
 
@@ -13,5 +14,6 @@ USER spring:spring
 
 WORKDIR /app
 COPY --from=build /app/target/app.jar app.jar
+COPY --from=build /app/opentelemetry-javaagent.jar opentelemetry-javaagent.jar
 EXPOSE 8080
-ENTRYPOINT ["java", "-jar", "app.jar"]
+ENTRYPOINT ["java", "-javaagent:opentelemetry-javaagent.jar", "-jar", "app.jar"]