add app details modal, refactor showing username logic, handle modals&pages in case of errors from input params, replace change theme button and etc..

src/utils/helpers/helpers.ts

@@ -127,3 +127,7 @@ export function getPermActionName(req: DbPerm) {
   }
   return action
 }
+
+export const isEmptyString = (str = '') => {
+  return str.trim().length === 0
+}