## Problem
It is called context/ctx everywhere and the Monitoring suffix needlessly
confuses with proper monitoring code.
## Summary of changes
* Rename RequestMonitoring to RequestContext
* Rename RequestMonitoringInner to RequestContextInner
See https://github.com/neondatabase/cloud/issues/14378
In collaboration with @cloneable and @awarus, we sifted through logs and
simply demoted some logs to debug. This is not at all finished and there
are more logs to review, but we ran out of time in the session we
organised. In any slightly more nuanced cases, we didn't touch the log,
instead leaving a TODO comment.
AWS/azure private link shares extra information in the "TLV" values of
the proxy protocol v2 header. This code doesn't action on it, but it
parses it as appropriate.
