Docker Client Mounting Settings Dir Deletes CMS Container `settings.py`

[wesleyboar]

Describe the bug
Local development of docker-based client of Core-CMS ¹ using the new …settings/ directory will destroy the CMS container's …settings/settings.py, thus breaking the CMS. The current solution is obtuse.

To Reproduce
Steps to reproduce the behavior:

1. Update a Core-CMS client (e.g. Core-Portal):
   1. Update CMS to v4.37.1.
   2. Migrate its settings overwrites:
      • from /taccsite/*.py
      • to /taccsite/settings/*.py
2. Build containers.
3. Start containers.
4. See errors caused by container not having /taccsite/settings.py.

Expected behavior
The container's /taccsite/settings.py is still present.

Tasks:

1. Refactor Core-CMS settings (again).
2. Update the 2 clients that already rely on the first refactor:
   • Replace docker-merge-settings.sh Solution with settings/overwrites Core-CMS-Template#27
   • Replace docker-merge-settings.sh Solution with settings/overwrites CTRN-CMS#4
3. Update Core-Portal:
   _{fix: WP-813 CMS customization fails (new progress in 2026) Core-Portal#1034}

Additional context

Technical summary:

• Problem: …settings:…settings/ volume mount overwrites CMS container …settings/settings.py
• Solution: …settings/overwrites:…settings/overwrites/ preserves CMS container …settings/settings.py

Footnotes

1. Core-Portal, APCD-CMS, Texascale-CMS, CTRN-CMS, future repos via Core-CMS-Template ↩