Improve UI stability for e2e

playwright.config.ts

@@ -2,7 +2,8 @@ import { defineConfig, devices } from '@playwright/test';
 
 export default defineConfig({
   testDir: './e2e',
-  fullyParallel: true,
+  fullyParallel: false,
+  workers: 4,
   retries: process.env.CI ? 2 : 0,
   use: {
     baseURL: 'http://127.0.0.1:4173',