Add accounts app: custom User, Member, families & guardianship

Introduce the foundational accounts app:
- Custom email-as-username User (AbstractBaseUser + PermissionsMixin) set
  as AUTH_USER_MODEL, decoupled from membership so children can be members
  without a login.
- Member model holding personal/roster data (names, contact email, phone +
  emergency phone via django-phonenumber-field, license number, DOB) with an
  optional link to a User.
- Family household grouping and directional Guardianship (guardian -> child)
  with uniqueness and no-self-guardian constraints.
- Custom UserAdmin plus Member/Family admin with inlines and autocomplete.
- Settings: register apps, AUTH_USER_MODEL, phonenumber defaults (BE/E164).
- Add CLAUDE.md and a tracked static/ directory.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

accounts/tests.py

@@ -0,0 +1,87 @@
+from django.core.exceptions import ValidationError
+from django.db import IntegrityError, transaction
+from django.test import TestCase
+
+from .models import Family, Guardianship, Member, User
+
+
+class UserManagerTests(TestCase):
+    def test_create_user_with_email(self):
+        user = User.objects.create_user(email="Parent@Example.com", password="pw")
+        self.assertEqual(user.email, "Parent@example.com")  # domain normalized
+        self.assertTrue(user.check_password("pw"))
+        self.assertFalse(user.is_staff)
+        self.assertFalse(user.is_superuser)
+
+    def test_create_superuser(self):
+        admin = User.objects.create_superuser(email="admin@example.com", password="pw")
+        self.assertTrue(admin.is_staff)
+        self.assertTrue(admin.is_superuser)
+
+    def test_create_user_requires_email(self):
+        with self.assertRaises(ValueError):
+            User.objects.create_user(email="", password="pw")
+
+    def test_create_superuser_rejects_non_superuser_flag(self):
+        with self.assertRaises(ValueError):
+            User.objects.create_superuser(email="a@b.com", password="pw", is_superuser=False)
+
+
+class MemberTests(TestCase):
+    def test_member_without_login_or_optional_fields(self):
+        member = Member.objects.create(
+            first_name="Kid",
+            last_name="Smith",
+            date_of_birth="2015-05-01",
+        )
+        self.assertIsNone(member.user)
+        self.assertEqual(member.email, "")
+        self.assertEqual(member.phone, "")
+        self.assertEqual(member.license_number, "")
+
+    def test_valid_phone_accepted(self):
+        member = Member(
+            first_name="Ann",
+            last_name="Smith",
+            date_of_birth="1980-01-01",
+            phone="+32470123456",
+        )
+        member.full_clean()  # should not raise
+
+    def test_invalid_phone_rejected(self):
+        member = Member(
+            first_name="Ann",
+            last_name="Smith",
+            date_of_birth="1980-01-01",
+            phone="not-a-number",
+        )
+        with self.assertRaises(ValidationError):
+            member.full_clean()
+
+
+class FamilyAndGuardianshipTests(TestCase):
+    def setUp(self):
+        self.family = Family.objects.create(name="The Smiths")
+        self.parent = Member.objects.create(
+            first_name="Ann", last_name="Smith", date_of_birth="1980-01-01", family=self.family
+        )
+        self.child = Member.objects.create(
+            first_name="Kid", last_name="Smith", date_of_birth="2015-05-01", family=self.family
+        )
+
+    def test_family_groups_members(self):
+        self.assertEqual(self.family.members.count(), 2)
+
+    def test_guardianship_relations_resolve(self):
+        Guardianship.objects.create(guardian=self.parent, child=self.child)
+        self.assertIn(self.parent, self.child.guardians.all())
+        self.assertIn(self.child, self.parent.dependents.all())
+
+    def test_no_self_guardianship(self):
+        with transaction.atomic(), self.assertRaises(IntegrityError):
+            Guardianship.objects.create(guardian=self.parent, child=self.parent)
+
+    def test_guardianship_is_unique(self):
+        Guardianship.objects.create(guardian=self.parent, child=self.child)
+        with transaction.atomic(), self.assertRaises(IntegrityError):
+            Guardianship.objects.create(guardian=self.parent, child=self.child)