UWP compiled naett with the WinHTTP backend but never reported
SYSPROP_SUPPORTS_HTTPS, so achievement traffic and badge icons went over
plain http. When the media server redirected to https, icons failed.
A failed icon download also left the URL marked pending, so it was never
retried for the rest of the session. Mark it failed instead, and let
IconCache retry it after 30 seconds.
The set-completed badge also skipped RemoveHttpsIfNeeded.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
It doesn't try to insert or fetch missing things itself, re-fetching is up to the caller.
This will be required for handling the many achievement icons.
Saving/loading the cache to a single file on disk is implemented but not
hooked up yet. It works without it, though of course will have to
re-fetch things on the next startup.
