feat: add multi-user admin panel and featured partners toggle on home page

app/admin/login/page.tsx

@@ -20,6 +20,18 @@ export default function LoginPage() {
                     </div>
 
                     <form action={formAction} className="space-y-6">
+                        <div className="space-y-2">
+                            <label className="text-[10px] font-bold uppercase tracking-widest text-white/40 ml-1">Kullanıcı Adı</label>
+                            <input
+                                type="text"
+                                name="username"
+                                defaultValue="admin"
+                                required
+                                className="w-full bg-white/5 border border-white/10 rounded-xl px-4 py-3 text-white placeholder:text-white/20 focus:border-[#1e9a83] focus:ring-1 focus:ring-[#1e9a83] outline-none transition-all"
+                                placeholder="örn: admin"
+                            />
+                        </div>
+
                         <div className="space-y-2">
                             <label className="text-[10px] font-bold uppercase tracking-widest text-white/40 ml-1">Şifre</label>
                             <input