[1.0.0] Metrics follow-up.

[ChadSikorra]

This is a follow-up to the metrics work to flesh out some stuff a bit more before moving on:

1. Record the idle timeout properly now that we have an actual marker from the freedsx/socket library.
2. Record a breakdown of the search types so we can distinguish between sub/read/list.
3. Record currently in-flight operations broken down by type.
4. Record traffic based stats (bytes sent / received, entries sent).
5. Record when the request size is exceeded.