Update weed/s3api/s3tables/handler.go

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

weed/s3api/s3tables/handler.go

@@ -161,6 +161,9 @@ func (h *S3TablesHandler) HandleRequest(w http.ResponseWriter, r *http.Request,
 // This is also used as the principal for permission checks, ensuring alignment between
 // the caller identity and ownership verification when IAM is enabled.
 func (h *S3TablesHandler) getAccountID(r *http.Request) string {
+	if identityName := s3_constants.GetIdentityNameFromContext(r.Context()); identityName != "" {
+		return identityName
+	}
 	if accountID := r.Header.Get(s3_constants.AmzAccountId); accountID != "" {
 		return accountID
 	}