Refactor user account system and remove moderation integration

- Remove first_name and last_name fields from User model
- Add user deletion and social provider services
- Restructure auth serializers into separate directory
- Update avatar upload functionality and API endpoints
- Remove django-moderation integration documentation
- Add mandatory compliance enforcement rules
- Update frontend documentation with API usage examples

backend/apps/api/v1/auth/models.py

@@ -1,33 +1,3 @@
-from django.db import models
-from django.conf import settings
-from django.utils import timezone
-
-
-class PasswordReset(models.Model):
-    """Persisted password reset tokens for API-driven password resets."""
-
-    user = models.ForeignKey(
-        settings.AUTH_USER_MODEL,
-        on_delete=models.CASCADE,
-        related_name="password_resets",
-    )
-    token = models.CharField(max_length=128, unique=True, db_index=True)
-    created_at = models.DateTimeField(auto_now_add=True)
-    expires_at = models.DateTimeField()
-    used = models.BooleanField(default=False)
-
-    class Meta:
-        ordering = ["-created_at"]
-        verbose_name = "Password Reset"
-        verbose_name_plural = "Password Resets"
-
-    def is_expired(self) -> bool:
-        return timezone.now() > self.expires_at
-
-    def mark_used(self) -> None:
-        self.used = True
-        self.save(update_fields=["used"])
-
-    def __str__(self):
-        user_id = getattr(self, "user_id", None)
-        return f"PasswordReset(user={user_id}, token={self.token[:8]}..., used={self.used})"
+# This file is intentionally empty.
+# All models are now in their appropriate apps to avoid conflicts.
+# PasswordReset model is available in apps.accounts.models