send cloudId during upload

# Conflicts:
#	mobile/lib/services/upload.service.dart

mobile/lib/domain/models/asset/metadata.model.dart

@@ -0,0 +1,20 @@
+import 'dart:convert';
+
+class AssetMetadata {
+  final String? cloudId;
+
+  const AssetMetadata({this.cloudId});
+
+  Map<String, dynamic> toMap() {
+    return {
+      "metadata": [
+        {
+          "key": "mobile-app",
+          "value": cloudId != null ? {"iCloudId": cloudId} : {},
+        },
+      ],
+    };
+  }
+
+  String toJson() => json.encode(toMap());
+}