[turegjorup]

Lets projects keep their own nginx rules in .docker/templates/server.d/ so template:update no longer overwrites them.

Changes

• templates/{drupal,symfony}/.docker/templates/default.conf.template: include /etc/nginx/conf.d/server.d/*.conf; in the server block (also used by drupal-10, drupal-11, symfony-6, symfony-7 and symfony-8 through symlinks)
• README.md: where to keep project-specific changes (docker-compose.override.yml, docker-compose.server.override.yml and .docker/templates/server.d/)
• CHANGELOG.md: add entry

Why

template:update copies the template files over the project's own, so project-specific lines in default.conf.template are lost on every update. For example, event-database-imports serves its admin under /admin and needs a rewrite for its assets. A template update removed that rewrite, and it had to be restored in itk-dev/event-database-imports@2f59b75. The same update removed it again today.

docker compose already has override files for this. nginx now has the same kind of override:

• The nginx image runs envsubst on *.template files in subfolders of /etc/nginx/templates and writes them to the same subfolder in conf.d. Project files in server.d/ therefore get the same variable substitution as default.conf.template.
• nginx only loads conf.d/*.conf, not subfolders, so server.d/*.conf is only used through the new include.
• template:update (rsync without --delete) leaves files the template doesn't ship, so server.d/ survives updates.
• An include with a wildcard that matches nothing is not an error. Both configs pass nginx -t with no server.d/ folder, so existing projects need no changes.

Tested in event-database-imports with the rewrite moved to .docker/templates/server.d/app-path-prefix.conf.template: admin assets and routes load under /admin (itk-dev/event-database-imports#116).

The EOL drupal-8 and drupal-9 templates are left unchanged.