refactor: Reorganize tests into tests/ directories

Follow cookiecutter-django convention by placing tests in dedicated
tests/ directories within each app instead of single tests.py files.

Changes:
- Created tests/ directories with __init__.py for all 13 apps
- Moved analytics/tests.py → analytics/tests/test_views.py
- Moved schedule/test_export.py → schedule/tests/test_export.py
- Moved platform/api/tests_token_security.py → platform/api/tests/test_token_security.py
- Deleted empty placeholder tests.py files

All apps now have a tests/ directory ready for proper test organization.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

smoothschedule/smoothschedule/commerce/payments/tests.py

@@ -1,3 +0,0 @@
-from django.test import TestCase
-
-# Create your tests here.

smoothschedule/smoothschedule/commerce/tickets/tests.py

@@ -1,3 +0,0 @@
-from django.test import TestCase
-
-# Create your tests here.

smoothschedule/smoothschedule/communication/messaging/tests.py

@@ -1,3 +0,0 @@
-from django.test import TestCase
-
-# Create your tests here.

smoothschedule/smoothschedule/communication/notifications/tests.py

@@ -1,3 +0,0 @@
-from django.test import TestCase
-
-# Create your tests here.

smoothschedule/smoothschedule/scheduling/contracts/tests.py

@@ -1,3 +0,0 @@
-from django.test import TestCase
-
-# Create your tests here.

smoothschedule/smoothschedule/scheduling/schedule/tests.py

@@ -1,3 +0,0 @@
-from django.test import TestCase
-
-# Create your tests here.