fix: control-plane 镜像缺少 migrations 目录导致数据库迁移不执行

Dockerfile 最终阶段只复制了二进制和 image.lock，
遗漏了 internal/store/migrations/ 目录，
导致启动时迁移器找不到 SQL 文件，新表无法创建。

Made-with: Cursor

Author: ZaneL1u

deploy/docker/control-plane/Dockerfile

@@ -19,6 +19,7 @@ RUN apt-get update \
 COPY --from=builder /usr/local/bin/control-plane /usr/local/bin/control-plane
 
 WORKDIR /app
+COPY internal/store/migrations internal/store/migrations
 COPY deploy/docker/managed-user/image.lock deploy/docker/managed-user/image.lock
 
 EXPOSE 8080