Add cuisine subcategory filter, fix remap logic, and add OKE deployment manifests

- Add 파인다이닝/코스 cuisine type to 한식/일식/중식/양식 categories
- Change cuisine filter from flat list to grouped optgroup with subcategories
- Fix remap-foods/remap-cuisine: add jdbcType=CLOB, fix CLOB LISTAGG,
  improve retry logic (3 attempts, batch size 5), add error logging
- Add OKE deployment: Dockerfiles, K8s manifests, deploy.sh, deployment guide
- Add Next.js standalone output for Docker builds

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend-java/Dockerfile

@@ -0,0 +1,16 @@
+# ── Build stage ──
+FROM eclipse-temurin:21-jdk AS build
+WORKDIR /app
+COPY gradlew settings.gradle build.gradle ./
+COPY gradle/ gradle/
+RUN chmod +x gradlew && ./gradlew dependencies --no-daemon || true
+COPY src/ src/
+RUN ./gradlew bootJar -x test --no-daemon
+
+# ── Runtime stage ──
+FROM eclipse-temurin:21-jre
+WORKDIR /app
+COPY --from=build /app/build/libs/*.jar app.jar
+EXPOSE 8000
+ENV JAVA_OPTS="-XX:MaxRAMPercentage=75.0 -XX:+UseG1GC"
+ENTRYPOINT ["sh", "-c", "java $JAVA_OPTS -jar app.jar"]