feat(scripts): 添加 APT 缓存预装功能解决离线构建问题

- 新增 APT 缓存目录和相关构建脚本 export-cache.sh
- 添加 build-base-images.sh 脚本用于构建预装 APT 包的基础镜像
- 增加 build-offline-final.sh 最终版离线构建脚本
- 更新 Makefile.offline.mk 添加新的离线构建目标
- 扩展 README.md 文档详细说明 APT 缓存问题解决方案
- 为多个服务添加使用预装基础镜像的离线 Dockerfile
- 修改打包脚本包含 APT 缓存到最终压缩包中

scripts/offline/Dockerfile.gateway.offline

@@ -0,0 +1,47 @@
+# gateway Dockerfile 离线版本
+FROM maven:3-eclipse-temurin-21 AS builder
+
+# 配置 Maven 阿里云镜像
+RUN mkdir -p /root/.m2 && \
+    echo '<?xml version="1.0" encoding="UTF-8"?>\n\
+<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"\n\
+          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"\n\
+          xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">\n\
+  <mirrors>\n\
+    <mirror>\n\
+      <id>aliyunmaven</id>\n\
+      <mirrorOf>*</mirrorOf>\n\
+      <name>阿里云公共仓库</name>\n\
+      <url>https://maven.aliyun.com/repository/public</url>\n\
+    </mirror>\n\
+  </mirrors>\n\
+</settings>' > /root/.m2/settings.xml
+
+WORKDIR /opt/gateway
+
+COPY backend/pom.xml ./
+COPY backend/api-gateway/pom.xml ./api-gateway/
+
+RUN --mount=type=cache,target=/root/.m2/repository \
+    cd /opt/gateway/api-gateway && \
+    mvn dependency:go-offline -Dmaven.test.skip=true || true
+
+COPY backend/api-gateway /opt/gateway/api-gateway
+
+RUN --mount=type=cache,target=/root/.m2/repository \
+    cd /opt/gateway/api-gateway && \
+    mvn clean package -Dmaven.test.skip=true
+
+FROM datamate-java-base:latest
+
+COPY --from=builder /opt/gateway/api-gateway/target/gateway.jar /opt/gateway/gateway.jar
+COPY scripts/images/gateway/start.sh /opt/gateway/start.sh
+
+RUN dos2unix /opt/gateway/start.sh \
+    && chmod +x /opt/gateway/start.sh \
+    && ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
+
+EXPOSE 8080
+
+ENTRYPOINT ["/opt/gateway/start.sh"]
+CMD ["java", "-Duser.timezone=Asia/Shanghai", "-jar", "/opt/gateway/gateway.jar"]