fix: 在 Dockerfile.goreleaser 中添加 pg_dump 和 psql 工具 #1002

为了支持容器内的数据库备份和恢复功能，在运行时镜像中添加 PostgreSQL 客户端工具。

变更内容：
- 使用多阶段构建从 postgres:18-alpine 镜像复制 pg_dump 和 psql 二进制文件
- 添加必要的依赖库（libpq, zstd-libs, lz4-libs, krb5-libs, libldap, libedit）
- 升级基础镜像到 alpine:3.21
- 复制 libpq.so.5 共享库以确保工具正常运行

这样可以在运行时容器中直接执行数据库备份和恢复操作，无需访问 Docker socket。

Dockerfile.goreleaser

@@ -5,7 +5,12 @@
 # It only packages the pre-built binary, no compilation needed.
 # =============================================================================
 
-FROM alpine:3.19
+ARG ALPINE_IMAGE=alpine:3.21
+ARG POSTGRES_IMAGE=postgres:18-alpine
+
+FROM ${POSTGRES_IMAGE} AS pg-client
+
+FROM ${ALPINE_IMAGE}
 
 LABEL maintainer="Wei-Shaw <github.com/Wei-Shaw>"
 LABEL description="Sub2API - AI API Gateway Platform"
@@ -16,8 +21,20 @@ RUN apk add --no-cache \
     ca-certificates \
     tzdata \
     curl \
+    libpq \
+    zstd-libs \
+    lz4-libs \
+    krb5-libs \
+    libldap \
+    libedit \
     && rm -rf /var/cache/apk/*
 
+# Copy pg_dump and psql from a version-matched PostgreSQL image so backup and
+# restore work in the runtime container without requiring Docker socket access.
+COPY --from=pg-client /usr/local/bin/pg_dump /usr/local/bin/pg_dump
+COPY --from=pg-client /usr/local/bin/psql /usr/local/bin/psql
+COPY --from=pg-client /usr/local/lib/libpq.so.5* /usr/local/lib/
+
 # Create non-root user
 RUN addgroup -g 1000 sub2api && \
     adduser -u 1000 -G sub2api -s /bin/sh -D sub2api