fix: display email instead of userid in admin panel

src/pages/Admin.tsx

@@ -6,6 +6,7 @@ import { api } from '../lib/api';
 
 interface UserProfile {
   id: string;
+  email: string;
   role: string;
   api_credits: number;
   storage_limit_mb: number;
@@ -84,7 +85,7 @@ export default function Admin() {
                <table className="w-full text-left text-sm">
                  <thead className="bg-zinc-950 text-zinc-400">
                    <tr>
-                     <th className="p-4 font-medium">User ID</th>
+                     <th className="p-4 font-medium">Email</th>
                      <th className="p-4 font-medium">Role</th>
                      <th className="p-4 font-medium">Status</th>
                      <th className="p-4 font-medium">API Credits</th>
@@ -124,7 +125,7 @@ const UserRow = ({ user, onUpdate }: { user: UserProfile, onUpdate: (u: UserProf
 
   return (
     <tr className="hover:bg-zinc-800/50">
-      <td className="p-4 font-mono text-xs">{user.id}</td>
+      <td className="p-4 font-mono text-xs">{user.email}</td>
       <td className="p-4">
         <select 
           value={role}