Add environment configuration and email settings

- Created a new .env.example file for environment variable configuration including Django settings, email configurations, and common SMTP provider examples.
- Updated .vscode/settings.json to include additional words for spell checking.
- Enhanced config/settings.py to load environment variables using python-dotenv, added data directory management, and configured email settings.
- Updated config/urls.py to include debug toolbar URLs conditionally based on testing.
- Added pytest configuration in conftest.py for Django testing.
- Created core application with custom User model, admin registration, and migrations.
- Implemented tests for User model and admin functionalities.
- Updated pyproject.toml to include new dependencies for debugging and environment management.
- Updated uv.lock to reflect new package versions and dependencies.

core/tests/test_admin.py

@@ -0,0 +1,86 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Any
+
+import pytest
+from django.contrib import admin
+from django.contrib.auth import get_user_model
+from django.contrib.auth.admin import UserAdmin
+from django.contrib.auth.models import AbstractUser
+from django.db.models.base import Model
+from django.test import RequestFactory
+
+if TYPE_CHECKING:
+    from django.contrib.admin import ModelAdmin
+    from django.contrib.auth.models import AbstractUser
+    from django.db.models.base import Model
+
+User: type[AbstractUser] = get_user_model()
+
+
+@pytest.mark.django_db
+class TestUserAdmin:
+    """Test cases for User admin configuration."""
+
+    def setup_method(self) -> None:
+        """Set up test data for each test method."""
+        self.factory = RequestFactory()
+        self.superuser: AbstractUser = User.objects.create_superuser(
+            username="admin",
+            email="admin@example.com",
+            password="test_admin_password_123",
+        )
+
+    def test_user_model_registered_in_admin(self) -> None:
+        """Test that User model is registered in Django admin."""
+        registry: dict[type[Model], ModelAdmin[Any]] = admin.site._registry  # noqa: SLF001
+        assert User in registry
+
+    def test_user_admin_class(self) -> None:
+        """Test that User is registered with UserAdmin."""
+        registry: dict[type[Model], ModelAdmin[Any]] = admin.site._registry  # noqa: SLF001
+        admin_class: admin.ModelAdmin[Any] = registry[User]
+        assert isinstance(admin_class, UserAdmin)
+
+    def test_user_admin_can_create_user(self) -> None:
+        """Test that admin can create users through the interface."""
+        # Test that the admin form can handle user creation
+        registry: dict[type[Model], ModelAdmin[Any]] = admin.site._registry  # noqa: SLF001
+        user_admin: admin.ModelAdmin[Any] = registry[User]
+
+        # Check that the admin has the expected methods
+        assert hasattr(user_admin, "get_form")
+        assert hasattr(user_admin, "save_model")
+
+    def test_user_admin_list_display(self) -> None:
+        """Test admin list display configuration."""
+        registry: dict[type[Model], ModelAdmin[Any]] = admin.site._registry  # noqa: SLF001
+        user_admin: admin.ModelAdmin[Any] = registry[User]
+
+        # UserAdmin should have default list_display
+        expected_fields: tuple[str, ...] = (
+            "username",
+            "email",
+            "first_name",
+            "last_name",
+            "is_staff",
+        )
+        assert user_admin.list_display == expected_fields
+
+    def test_user_admin_search_fields(self) -> None:
+        """Test admin search fields configuration."""
+        registry: dict[type[Model], ModelAdmin[Any]] = admin.site._registry  # noqa: SLF001
+        user_admin: admin.ModelAdmin[Any] = registry[User]
+
+        # UserAdmin should have default search fields
+        expected_search_fields: tuple[str, ...] = ("username", "first_name", "last_name", "email")
+        assert user_admin.search_fields == expected_search_fields
+
+    def test_user_admin_fieldsets(self) -> None:
+        """Test admin fieldsets configuration."""
+        registry: dict[type[Model], ModelAdmin[Any]] = admin.site._registry  # noqa: SLF001
+        user_admin: admin.ModelAdmin[Any] = registry[User]
+
+        # UserAdmin should have fieldsets defined
+        assert hasattr(user_admin, "fieldsets")
+        assert user_admin.fieldsets is not None

core/tests/test_models.py

@@ -0,0 +1,178 @@
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+import pytest
+from django.contrib.auth import get_user_model
+from django.contrib.auth.models import AbstractUser
+from django.core.exceptions import ValidationError
+from django.db import IntegrityError
+
+if TYPE_CHECKING:
+    from django.contrib.auth.models import AbstractUser
+
+User: type[AbstractUser] = get_user_model()
+
+
+@pytest.mark.django_db
+class TestUserModel:
+    """Test cases for the custom User model."""
+
+    def test_create_user(self) -> None:
+        """Test creating a regular user."""
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com", password="testpass123")
+
+        assert user.username == "testuser"
+        assert user.email == "test@example.com"
+        assert user.check_password("testpass123")
+        assert not user.is_staff
+        assert not user.is_superuser
+        assert user.is_active
+
+    def test_create_superuser(self) -> None:
+        """Test creating a superuser."""
+        superuser: AbstractUser = User.objects.create_superuser(username="admin", email="admin@example.com", password="adminpass123")
+
+        assert superuser.username == "admin"
+        assert superuser.email == "admin@example.com"
+        assert superuser.check_password("adminpass123")
+        assert superuser.is_staff
+        assert superuser.is_superuser
+        assert superuser.is_active
+
+    def test_user_str_representation(self) -> None:
+        """Test the string representation of the user."""
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com")
+
+        assert str(user) == "testuser"
+
+    def test_user_email_field(self) -> None:
+        """Test that email field works correctly."""
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com", password="testpass123")
+
+        assert user.email == "test@example.com"
+
+        # Test email update
+        user.email = "newemail@example.com"
+        user.save()
+        user.refresh_from_db()
+
+        assert user.email == "newemail@example.com"
+
+    def test_user_unique_username(self) -> None:
+        """Test that username must be unique."""
+        User.objects.create_user(username="testuser", email="test1@example.com", password="testpass123")
+
+        # Attempting to create another user with the same username should raise an error
+        with pytest.raises(IntegrityError):
+            User.objects.create_user(username="testuser", email="test2@example.com", password="testpass123")
+
+    def test_user_password_hashing(self) -> None:
+        """Test that passwords are properly hashed."""
+        password = "testpass123"
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com", password=password)
+
+        # Password should be hashed, not stored in plain text
+        assert user.password != password
+        assert user.check_password(password)
+        assert not user.check_password("wrongpassword")
+
+    def test_user_without_email(self) -> None:
+        """Test creating a user without email."""
+        user: AbstractUser = User.objects.create_user(username="testuser", password="testpass123")
+
+        assert user.username == "testuser"
+        assert not user.email
+        assert user.check_password("testpass123")
+
+    def test_user_model_meta_options(self) -> None:
+        """Test the model meta options."""
+        assert User._meta.db_table == "auth_user"  # noqa: SLF001
+        assert User._meta.verbose_name == "User"  # noqa: SLF001
+        assert User._meta.verbose_name_plural == "Users"  # noqa: SLF001
+
+    def test_user_manager_methods(self) -> None:
+        """Test User manager methods."""
+        # Test create_user method
+        user: AbstractUser = User.objects.create_user(username="regularuser", email="regular@example.com", password="pass123")
+        assert not user.is_staff
+        assert not user.is_superuser
+
+        # Test create_superuser method
+        superuser: AbstractUser = User.objects.create_superuser(username="superuser", email="super@example.com", password="superpass123")
+        assert superuser.is_staff
+        assert superuser.is_superuser
+
+    def test_user_permissions(self) -> None:
+        """Test user permissions and groups."""
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com", password="testpass123")
+
+        # Initially user should have no permissions
+        assert not user.user_permissions.exists()
+        assert not user.groups.exists()
+
+        # Test has_perm method (should be False for regular user)
+        assert not user.has_perm("auth.add_user")
+
+    def test_user_active_status(self) -> None:
+        """Test user active status functionality."""
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com", password="testpass123")
+
+        # User should be active by default
+        assert user.is_active
+
+        # Test deactivating user
+        user.is_active = False
+        user.save()
+        user.refresh_from_db()
+
+        assert not user.is_active
+
+    def test_user_date_joined(self) -> None:
+        """Test that date_joined is automatically set."""
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com", password="testpass123")
+
+        assert user.date_joined is not None
+
+    def test_user_last_login_initially_none(self) -> None:
+        """Test that last_login is initially None."""
+        user: AbstractUser = User.objects.create_user(username="testuser", email="test@example.com", password="testpass123")
+
+        assert user.last_login is None
+
+
+@pytest.mark.django_db
+class TestUserModelEdgeCases:
+    """Test edge cases and error conditions for the User model."""
+
+    def test_create_user_without_username(self) -> None:
+        """Test that creating a user without username raises an error."""
+        with pytest.raises(ValueError, match="The given username must be set"):
+            User.objects.create_user(username="", email="test@example.com", password="testpass123")
+
+    def test_create_superuser_without_is_staff(self) -> None:
+        """Test that create_superuser enforces is_staff=True."""
+        with pytest.raises(ValueError, match=r"Superuser must have is_staff=True."):
+            User.objects.create_superuser(username="admin", email="admin@example.com", password="adminpass123", is_staff=False)
+
+    def test_create_superuser_without_is_superuser(self) -> None:
+        """Test that create_superuser enforces is_superuser=True."""
+        with pytest.raises(ValueError, match=r"Superuser must have is_superuser=True."):
+            User.objects.create_superuser(username="admin", email="admin@example.com", password="adminpass123", is_superuser=False)
+
+    def test_user_with_very_long_username(self) -> None:
+        """Test username length validation."""
+        # Django's default max_length for username is 150
+        long_username: str = "a" * 151
+
+        user = User(username=long_username, email="test@example.com")
+
+        with pytest.raises(ValidationError):
+            user.full_clean()
+
+    def test_user_with_invalid_email_format(self) -> None:
+        """Test email format validation."""
+        user = User(username="testuser", email="invalid-email-format")
+
+        with pytest.raises(ValidationError):
+            user.full_clean()