feat(dto): create UserDTO for user data transfer

Author: OtavioXimarelli

src/main/java/com/otavio/aifoodapp/dto/UserDTO.java

@@ -0,0 +1,19 @@
+package com.otavio.aifoodapp.dto;
+
+import com.otavio.aifoodapp.model.User;
+
+public record UserDTO(
+        Long id,
+        String email,
+        String name,
+        String role
+) {
+    public static UserDTO fromUser(User user) {
+        return new UserDTO(
+                user.getId(),
+                user.getEmail(),
+                user.getUsername(),
+                user.getRole() != null ? user.getRole().toString() : "USER"
+        );
+    }
+}