Docs: a config update is not visible to locations the server already loaded #507

UpdateConfigAsync (204) writes the global config, but GetConfigAsync for a location the server already serves returns the old view. A fresh location or a server restart sees the change at once.

Proposed: check upstream's behaviour at the pin first. Then say so on UpdateConfigAsync and name the refresh path: location eviction or a restart.

Source: internal developer-experience evaluation of the 2.0.32 nightly, 2026-10-18 (finding D32-4).