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/shared/objectstorage/url_test.go

@@ -51,3 +51,23 @@ func TestNormalizeObjectKeyPathDecodesEncodedSegments(t *testing.T) {
 		t.Fatalf("object key = %q, want %q", got, want)
 	}
 }
+
+func TestDownloadContentDispositionUsesRFC5987FileName(t *testing.T) {
+	t.Parallel()
+
+	got := DownloadContentDisposition("reports/省心推 安装包.zip")
+	want := `attachment; filename="object.zip"; filename*=UTF-8''%E7%9C%81%E5%BF%83%E6%8E%A8%20%E5%AE%89%E8%A3%85%E5%8C%85.zip`
+	if got != want {
+		t.Fatalf("content disposition = %q, want %q", got, want)
+	}
+}
+
+func TestDownloadContentDispositionKeepsASCIIFileNameFallback(t *testing.T) {
+	t.Parallel()
+
+	got := DownloadContentDisposition(`reports/report "final".csv`)
+	want := `attachment; filename="report final.csv"; filename*=UTF-8''report%20final.csv`
+	if got != want {
+		t.Fatalf("content disposition = %q, want %q", got, want)
+	}
+}