feat(server) user-defined storage structure (#1098)

[Breaking] newly uploaded file will conform to the default structure of `{uploadLocation}/{userId}/year/year-month-day/filename.ext`

mobile/openapi/test/system_config_api_test.dart

@@ -27,6 +27,11 @@ void main() {
       // TODO
     });
 
+    //Future<SystemConfigTemplateStorageOptionDto> getStorageTemplateOptions() async
+    test('test getStorageTemplateOptions', () async {
+      // TODO
+    });
+
     //Future<SystemConfigDto> updateConfig(SystemConfigDto systemConfigDto) async
     test('test updateConfig', () async {
       // TODO