fix: 修复后端服务配置文件路径和Docker镜像问题

- 修复配置文件路径错误：etc/photographyapi-api.yaml -> etc/photography-api.yaml
- 修复Dockerfile未包含配置文件的问题
- 确保后端服务容器能正确加载配置文件

修复了容器启动时报'config file etc/photographyapi-api.yaml: no such file or directory'的错误

backend/Dockerfile

@@ -53,6 +53,7 @@ COPY --from=builder /app/migrate /migrate
 COPY --from=builder /app/configs /configs
 COPY --from=builder /app/scripts /scripts
 COPY --from=builder /app/pkg/migration /pkg/migration
+COPY --from=builder /app/etc /etc
 
 # 设置时区
 ENV TZ=Asia/Shanghai