feature: init kotlin compose multiplatforme

docker/Dockerfile

@@ -2,9 +2,11 @@
 FROM gradle:9.6.1-jdk21-alpine AS cache
 RUN mkdir -p /home/gradle/cache_home
 ENV GRADLE_USER_HOME=/home/gradle/cache_home
-COPY build.gradle.* gradle.properties /home/gradle/app/
+COPY settings.gradle.kts build.gradle.kts gradle.properties /home/gradle/app/
+COPY backend/build.gradle.kts /home/gradle/app/backend/
+COPY shared/build.gradle.kts /home/gradle/app/shared/
 WORKDIR /home/gradle/app
-RUN gradle build -i -x check
+RUN gradle :backend:build -i -x check
 
 # Stage 2: Build Application
 FROM gradle:9.6.1-jdk21-alpine AS build
@@ -13,11 +15,11 @@ COPY --chown=gradle:gradle . /home/gradle/src
 WORKDIR /home/gradle/src
 # Build the fat JAR, Gradle also supports shadow
 # and boot JAR by default.
-RUN gradle buildFatJar --no-daemon
+RUN gradle :backend:buildFatJar --no-daemon
 
 # Stage 3: Create the Runtime Image
 FROM eclipse-temurin:21-jre-alpine AS runtime
 EXPOSE 8080
 RUN mkdir /app
-COPY --from=build /home/gradle/src/build/libs/*-all.jar /app/event-demo-all.jar
+COPY --from=build /home/gradle/src/backend/build/libs/*-all.jar /app/event-demo-all.jar
 ENTRYPOINT ["java","-jar","/app/event-demo-all.jar"]