refactor(settings):调整浏览器池大小默认值

-将 BrowserPoolSize 的默认值从 3 修改为 1
- 确保在设置值小于等于 0 时，使用新的默认值 1

backend/data/settings_api.go

@@ -125,7 +125,7 @@ func (s SettingsApi) GetConfig() *Settings {
 		settings.BrowserPath, _ = CheckBrowserOnWindows()
 	}
 	if settings.BrowserPoolSize <= 0 {
-		settings.BrowserPoolSize = 3
+		settings.BrowserPoolSize = 1
 	}
 	return &settings
 }