Valgrind Massif profiling revealed that invoking Gtk::IconTheme::rescan_if_needed() inside SNI updateImage() and getIconByName() loops caused considerable memory churn and potential filesystem stat overhead whenever a system tray app pushed a metadata update.
This commit removes the rescan polling from the SNI proxy callback pipeline and the DefaultGtkIconThemeWrapper, restricting icon theme caching to load boundaries.
Signed-off-by: Austin Horstman <khaneliman12@gmail.com>