First commit of claude's rework in django + vanillajs fronted

apps/users/models.py

@@ -0,0 +1,31 @@
+from django.contrib.auth.models import AbstractUser
+from django.db import models
+
+
+LANGUAGE_CHOICES = [
+    ('en', 'English'),
+    ('fr', 'Français'),
+    ('de', 'Deutsch'),
+    ('es', 'Español'),
+]
+
+
+class User(AbstractUser):
+    """
+    Custom user model — kept intentionally thin so the schema can evolve.
+    Authentication is handled by dj-rest-auth + allauth (JWT + external IDP).
+    """
+    email = models.EmailField(unique=True)
+    avatar = models.ForeignKey(
+        'photos.Photo',
+        null=True, blank=True,
+        on_delete=models.SET_NULL,
+        related_name='avatar_user',
+    )
+    language = models.CharField(max_length=5, choices=LANGUAGE_CHOICES, default='en', verbose_name='language')
+
+    USERNAME_FIELD = 'email'
+    REQUIRED_FIELDS = ['username']
+
+    def __str__(self):
+        return self.email