fix: clarify seedance reference video failures

handler/media_reference.go

@@ -117,7 +117,25 @@ func ReferenceMedia(w http.ResponseWriter, r *http.Request, id string) {
 }
 
 func referenceMediaDir() string {
-	return filepath.Join("data", "reference-media")
+	return filepath.Join(referenceDataDir(), "reference-media")
+}
+
+func referenceDataDir() string {
+	driver := strings.ToLower(strings.TrimSpace(config.Cfg.StorageDriver))
+	dsn := strings.TrimSpace(config.Cfg.DatabaseDSN)
+	if (driver == "" || driver == "sqlite") && dsn != "" && dsn != ":memory:" && !strings.HasPrefix(dsn, "file:") {
+		pathPart := dsn
+		if index := strings.Index(dsn, "?"); index >= 0 {
+			pathPart = dsn[:index]
+		}
+		if filepath.IsAbs(pathPart) {
+			return filepath.Dir(pathPart)
+		}
+	}
+	if _, err := os.Stat("/app/data"); err == nil {
+		return "/app/data"
+	}
+	return "data"
 }
 
 func normalizeReferenceMediaType(contentType string, ext string) (string, string, bool) {