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/models.py

@@ -0,0 +1,21 @@
+from __future__ import annotations
+
+from django.contrib.auth.models import AbstractUser
+
+
+class User(AbstractUser):
+    """Custom User model extending Django's AbstractUser.
+
+    This allows for future customization of the User model
+    while maintaining all the default Django User functionality.
+    """
+
+    # Add any custom fields here in the future
+    # For example:
+    # bio = models.TextField(max_length=500, blank=True)
+    # avatar = models.ImageField(upload_to='avatars/', blank=True, null=True)
+
+    class Meta:
+        db_table = "auth_user"  # Keep the same table name as Django's default User
+        verbose_name = "User"
+        verbose_name_plural = "Users"