Refactor accounts app into authentication and club apps

- Split the accounts app into new authentication and club apps for better separation of concerns.
- Migrate the custom User, Member, and Family models to the authentication app.
- Introduce Club and ClubMembership models in the club app.
- Refactor Family model to use UUID as the primary key and consolidate family-role relationships into a new FamilyMembership model.
- Update tests, managers, and migrations to align with the new structure.

authentication/models.py

@@ -0,0 +1,128 @@
+import uuid
+
+from django.conf import settings
+from django.contrib.auth.base_user import AbstractBaseUser
+from django.contrib.auth.models import PermissionsMixin
+from django.db import models
+from django.utils.translation import gettext_lazy as _
+from phonenumber_field.modelfields import PhoneNumberField
+
+from clubmanager.base import UUIDModel
+
+from .managers import UserManager
+
+
+class User(AbstractBaseUser, PermissionsMixin):
+    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
+    email = models.EmailField(unique=True, db_index=True)
+
+    is_staff = models.BooleanField(default=False)
+    is_active = models.BooleanField(default=True)
+
+    objects = UserManager()
+
+    USERNAME_FIELD = "email"
+    REQUIRED_FIELDS = []
+
+    class Meta:
+        verbose_name = _("user")
+        verbose_name_plural = _("users")
+        ordering = ["email"]
+
+    def __str__(self):
+        return self.get_full_name()
+
+    def get_full_name(self):
+        member = getattr(self, "member", None)
+        if member is not None:
+            return member.get_full_name()
+        return self.email
+
+    def get_short_name(self):
+        member = getattr(self, "member", None)
+        if member is not None:
+            return member.get_short_name()
+        return self.email
+
+
+class Family(UUIDModel):
+    name = models.CharField(max_length=255)
+
+    class Meta:
+        verbose_name = _("family")
+        verbose_name_plural = _("families")
+        ordering = ["name"]
+
+    def __str__(self):
+        return self.name
+
+    @property
+    def guardians(self):
+        return Member.objects.filter(
+            family_memberships__family=self,
+            family_memberships__role__in=[FamilyMembership.FamilyRole.PARENT, FamilyMembership.FamilyRole.GUARDIAN],
+        )
+
+    @property
+    def children(self):
+        return Member.objects.filter(
+            family_memberships__family=self,
+            family_memberships__role=FamilyMembership.FamilyRole.CHILD,
+        )
+
+
+class Member(UUIDModel):
+    user = models.OneToOneField(settings.AUTH_USER_MODEL, on_delete=models.SET_NULL, related_name="member", null=True, blank=True)
+
+    first_name = models.CharField(max_length=150)
+    last_name = models.CharField(max_length=150)
+
+    date_of_birth = models.DateField(null=True, blank=True)
+
+    email = models.EmailField(blank=True)
+    phone = PhoneNumberField(null=True, blank=True)
+    emergency_phone = PhoneNumberField(null=True, blank=True)
+
+    class Meta:
+        verbose_name = _("member")
+        verbose_name_plural = _("members")
+        ordering = ["last_name", "first_name"]
+        indexes = [models.Index(fields=["last_name", "first_name"])]
+
+    def __str__(self):
+        return f"{self.first_name} {self.last_name}"
+
+    def get_full_name(self):
+        return f"{self.first_name} {self.last_name}".strip()
+
+    def get_short_name(self):
+        return self.first_name
+
+    @property
+    def guardians(self):
+        return Member.objects.filter(
+            family_memberships__role__in=[FamilyMembership.FamilyRole.PARENT, FamilyMembership.FamilyRole.GUARDIAN],
+            family_memberships__family__memberships__member=self,
+            family_memberships__family__memberships__role=FamilyMembership.FamilyRole.CHILD,
+        ).distinct()
+
+
+class FamilyMembership(models.Model):
+    class FamilyRole(models.TextChoices):
+        PARENT = "parent", _("parent")
+        CHILD = "child", _("child")
+        GUARDIAN = "guardian", _("guardian")
+        OTHER = "other", _("other")
+
+    family = models.ForeignKey(Family, on_delete=models.CASCADE, related_name="memberships")
+    member = models.ForeignKey(Member, on_delete=models.CASCADE, related_name="family_memberships")
+    role = models.CharField(max_length=255, choices=FamilyRole.choices, default=FamilyRole.PARENT)
+
+    class Meta:
+        verbose_name = _("family membership")
+        verbose_name_plural = _("family memberships")
+        ordering = ["family", "role", "member__last_name", "member__first_name"]
+        unique_together = ("family", "member")
+
+    def __str__(self):
+        return f"{self.family} - {self.member} ({self.get_role_display()})"