Detect custom domains by comparing the request host to the app host and apply
the tightened CSP there too, not just on the public path. Run the middleware
before express.static so static-served root documents get the header, and keep
helmet after static so its default-src does not block custom domain API calls.
Layer a stricter Content-Security-Policy on the /status/public document so
custom CSS cannot load external images, fonts, or stylesheets. Browsers
enforce the intersection of all CSP headers, so this only narrows the public
status page and never loosens the global policy, while keeping the app's
Google Fonts. Browser-enforced backstop behind the validator.
## Changes
- Swagger UI now prepends the current server URL (protocol + host) to
the servers list, so it works correctly in remote/Docker environments
instead of always pointing to localhost.
## Closes
Fixes#3339
Alex Holliday
Arnaud GRIMBERT
Buco7854
Ian Troisi
gorkem-bwl