Frontend added environment

react-frontend/.env.example

@@ -0,0 +1 @@
+backend_url=https://s.tzgyn.com

react-frontend/src/App.tsx

@@ -26,7 +26,7 @@ import { useToast } from '@/components/ui/use-toast'
 
 import { useEffect, useState } from 'react'
 
-const backend_url = 'http://192.168.100.40:3000'
+const backend_url = process.env.backend_url ?? 'http://192.168.100.40:3000'
 
 type Shortener = {
 	id: number