feat: replace custom login/signup with NextAuth credentials provider, add signup page using Prisma, update NextAuth config to JWT strategy

pages/signup.jsx

@@ -12,28 +12,26 @@ export default function SignUp() {
   const handleSubmit = async (e) => {
     e.preventDefault()
     setError("")
-    
-    if (password !== confirmPassword) {
-      setError("Senhas não coincidem")
-      return
-    }
-    
-    if (password.length < 6) {
-      setError("Senha deve ter pelo menos 6 caracteres")
-      return
-    }
-    
     setLoading(true)
-    
     try {
-      const res = await fetch("/api/auth/signup", {
+      if (password !== confirmPassword) {
+        setError("Senhas não coincidem")
+        return
+      }
+
+      if (password.length < 6) {
+        setError("Senha deve ter pelo menos 6 caracteres")
+        return
+      }
+
+      const res = await fetch("/api/auth/register", {
         method: "POST",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify({ username, password })
       })
-      
+
       const data = await res.json()
-      
+
       if (res.ok) {
         router.push("/signin")
       } else {
@@ -52,7 +50,7 @@ export default function SignUp() {
         <h2 className="text-2xl font-bold mb-6">Cadastrar - 1000Apps</h2>
         
         {error && (
-          <div className="bg-red-100 text-red-700 p-3 rounded mb-4">
+          <div className="mb-4 bg-red-100 text-red-700 p-3 rounded">
             {error}
           </div>
         )}
@@ -61,30 +59,30 @@ export default function SignUp() {
           <input
             type="text"
             placeholder="Nome de usuário"
+            className="w-full p-2 border rounded"
             value={username}
             onChange={(e) => setUsername(e.target.value)}
-            className="w-full p-2 border rounded"
             required
           />
           <input
             type="password"
             placeholder="Senha"
+            className="w-full p-2 border rounded"
             value={password}
             onChange={(e) => setPassword(e.target.value)}
-            className="w-full p-2 border rounded"
             required
             minLength={6}
           />
           <input
             type="password"
             placeholder="Confirmar senha"
+            className="w-full p-2 border rounded"
             value={confirmPassword}
             onChange={(e) => setConfirmPassword(e.target.value)}
-            className="w-full p-2 border rounded"
             required
           />
           <button 
-            type="submit" 
+            type="submit"
             disabled={loading}
             className="w-full bg-green-600 text-white py-2 rounded-lg disabled:opacity-50"
           >