feat: update social media links in Footer component to use environment variables and refactor Contact component to utilize backend URL from environment variable

frontend/src/app/components/sections/Contact.tsx

@@ -8,6 +8,7 @@ export default function Contact() {
   const t = useTranslations('contact');
   const [formData, setFormData] = useState<{ name: string; email: string; message: string }>({ name: '', email: '', message: '' });
   const [isSubmitting, setIsSubmitting] = useState(false);
+  const backendUrl = process.env.NEXT_PUBLIC_BACKEND_URL || 'http://localhost:3001';
 
   const handleChange = (e: React.ChangeEvent<HTMLInputElement | HTMLTextAreaElement>) => {
     setFormData({...formData, [e.target.name]: e.target.value });
@@ -29,9 +30,8 @@ export default function Contact() {
     }
 
     const submissionPromise = async () => {
-      //const backendUrl = process.env.NEXT_PUBLIC_BACKEND_URL;
       try {
-        const response = await fetch(`http://localhost:3001/api/email/send`, {
+        const response = await fetch(`${backendUrl}/api/email/send`, {
           method: 'POST',
           headers: { 'Content-Type': 'application/json' },
           body: JSON.stringify(formData),