Refactor Django settings module and environment configuration

- Move settings to a modular configuration structure
- Update environment variables in .env.example
- Modify DJANGO_SETTINGS_MODULE references across project files
- Simplify and standardize environment variable naming

apibase/asgi.py

@@ -11,6 +11,6 @@ import os
 
 from django.core.asgi import get_asgi_application
 
-os.environ.setdefault("DJANGO_SETTINGS_MODULE", "apibase.settings")
+os.environ.setdefault("DJANGO_SETTINGS_MODULE", "apibase.django.local")
 
 application = get_asgi_application()