- Currently, we create a request ID for internal use if one isn't set & this is used in logs
- If a custom request ID is set via X-Request-ID header, this gets logged, however, we don't return this with the response
- Means that a custom ID gets lost on the way back out, and makes tracing requests through a system trickier
- This change ensures that if X-Request-ID is set on the request, it is also set on the response so that requests can be properly traced
- It's easy to set this in e.g. nginx so that the feature becomes available - Ghost doens't need to do this
- Note: also split request id handling out into new middleware
refs #9178
- move express apps to one place (called `web`)
- requires https://github.com/TryGhost/Ghost-Admin/pull/923
- any further improvements are not part of this PR
- this PR just moves the files and ensures the paths are up-to-date
