[Feature request] log output enhancment

Is your feature request related to a problem? Please describe.

I wonder if it might be possible to add a funcionality that allows to enhance the log output.

In detail: I use a log system to collect related log entries from different systems, starting with the reverse proxy and including a handful of backend systems. Identification of the log entries is done by setting a custom header on the reverse proxy which is then passed to all systems in upstream. This way the log system can correlate the log entries from the different systems.

Solution you would like.

I see the log entries are key/value entries in json and the solution I have in mind is to have an option to define a http header that is then, with its name and value, added to the log entries.

Describe alternatives you have considered.

No response

Additional context

No response