Refactor: Clean up settings files to eliminate duplication

- Remove duplicate FRONTEND_URL from base.py (was defined twice)
- Move LOGGING configuration from base.py to production.py (production-specific)
- Keep base.py minimal with only universal settings
- Verify EMAIL and AWS/STORAGES are production-only
- Update multitenancy.py import to not reference LOGGING from base.py

This ensures proper separation of concerns:
- base.py: Universal settings (DATABASES, CORS, CSRF, SECURITY basics)
- local.py: Development-specific (CSP, debug tools, console email, eager celery)
- production.py: Production-specific (LOGGING, EMAIL, AWS/S3, SECURITY headers, Sentry)

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

smoothschedule/config/settings/multitenancy.py

@@ -4,7 +4,7 @@ This file extends base.py and adds django-tenants configuration
 """
 
 from .base import *  # noqa
-from .base import INSTALLED_APPS, MIDDLEWARE, DATABASES, LOGGING, env
+from .base import INSTALLED_APPS, MIDDLEWARE, DATABASES, env
 
 # =============================================================================
 # MULTI-TENANCY CONFIGURATION (django-tenants)