feat(ops): add object storage management and site-mapping CSV import/export

Ship the Ops backstage 对象存储 page (browse / upload / move / delete /
folder ops) backed by a new object-storage service + handler, with the
shared storage client extended with List/Stat/Copy/Usage/DownloadURL so
both MinIO and Aliyun providers cover the new surface. Add
ForcePathStyle to the object-storage config and treat r2/s3/custom_s3
as external providers so Cloudflare R2 and other S3-compatibles can
share the MinIO client path without spinning up the bundled MinIO.

Also add CSV import/export + template download to the site-domain
mappings page, raise gin MaxMultipartMemory to 8 MiB for the new
multipart endpoints, register Ops swagger routes, and extend the
descriptions-parity test to cover the ops router.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

server/internal/ops/transport/site_domain_mapping_handler.go

@@ -1,7 +1,11 @@
 package transport
 
 import (
+	"fmt"
+	"io"
+	"net/http"
 	"strconv"
+	"time"
 
 	"github.com/gin-gonic/gin"
 
@@ -38,6 +42,58 @@ func listSiteDomainMappingsHandler(svc *app.SiteDomainMappingService) gin.Handle
 	}
 }
 
+func exportSiteDomainMappingsHandler(svc *app.SiteDomainMappingService) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		data, err := svc.ExportCSV(c.Request.Context(), actorFromGin(c), app.SiteDomainMappingListInput{
+			Keyword:  c.Query("keyword"),
+			IsActive: parseOptionalBoolQuery(c.Query("is_active")),
+		})
+		if err != nil {
+			response.Error(c, err)
+			return
+		}
+		fileName := fmt.Sprintf("site-domain-mappings-%s.csv", time.Now().Format("20060102150405"))
+		c.Header("Content-Type", "text/csv; charset=utf-8")
+		c.Header("Content-Disposition", fmt.Sprintf(`attachment; filename="%s"`, fileName))
+		c.Data(http.StatusOK, "text/csv; charset=utf-8", data)
+	}
+}
+
+func importSiteDomainMappingsHandler(svc *app.SiteDomainMappingService) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		fileHeader, err := c.FormFile("file")
+		if err != nil {
+			response.Error(c, response.ErrBadRequest(40057, "missing_site_domain_mapping_import_file", "请选择 CSV 文件"))
+			return
+		}
+		file, err := fileHeader.Open()
+		if err != nil {
+			response.Error(c, err)
+			return
+		}
+		defer file.Close()
+
+		content, err := io.ReadAll(io.LimitReader(file, 2*1024*1024+1))
+		if err != nil {
+			response.Error(c, err)
+			return
+		}
+		if len(content) > 2*1024*1024 {
+			response.Error(c, response.ErrBadRequest(40058, "site_domain_mapping_import_file_too_large", "CSV 文件不能超过 2MB"))
+			return
+		}
+
+		result, err := svc.ImportCSV(c.Request.Context(), actorFromGin(c), app.SiteDomainMappingImportInput{
+			Content: content,
+		})
+		if err != nil {
+			response.Error(c, err)
+			return
+		}
+		response.Success(c, result)
+	}
+}
+
 func createSiteDomainMappingHandler(svc *app.SiteDomainMappingService) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		var body siteDomainMappingRequest