[Game] Follow the palette in judge message tags (#7597)

* [Settings] Delete update channels at shutdown

SettingsCache owns the stable and beta update channels as raw pointers, and
each owns a QNetworkAccessManager, so the process leaves QtNetwork objects
alive past QApplication teardown.

Delete them from a QCoreApplication::aboutToQuit handler instead of the
destructor: SettingsCache is a Q_GLOBAL_STATIC, so ~SettingsCache() runs
during static teardown, after QApplication is gone, and destroying the
network managers at that point is the post-application window that ASan
reports. The hook is installed on the first instance() call that has an
application object, since the first access may predate it.

* [Game] Follow the palette in judge message tags

Judge tags hardcoded a black prefix and a `theme:icons/scales` image inside rich
text, where `currentColor` cannot resolve and a palette change leaves the tag
unreadable. Render the scales glyph through the themed icon engine, register it
as a document image resource, and repaint the log when the palette or theme
changes.

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Co-authored-by: Lukas Brübach <Bruebach.Lukas@bdosecurity.de>

cockatrice/src/game_graphics/log/message_log_widget.h

@@ -39,8 +39,10 @@ private:
 
     MessageContext currentContext;
     QString messagePrefix, messageSuffix;
+    QString contextJudgeName;
 
     static QPair<QString, QString> getFromStr(CardZoneLogic *zone, QString cardName, int position, bool ownerChange);
+    void refreshJudgeSuffix();
 
 public:
     void connectToPlayerEventHandler(PlayerEventHandler *player);