Reach nodes by unique name instead of long paths

Nodes a script uses through a path of several nodes are marked unique in their
scene and found with %Name. The search list is renamed SearchResults, and the
player row's nodes get their real types.

main_window.gd

@@ -33,7 +33,7 @@ var log_popup: LogPopup = %LogPopup
 var statistic_popup: PopupPanel = $StatisticsPopupPanel
 
 @onready
-var statistic_label: Label = $StatisticsPopupPanel/StatisticsLabel
+var statistic_label: Label = %StatisticsLabel
 
 ## Dims the window behind an open popup and keeps clicks from reaching the buttons under it.
 var popup_backdrop: PopupBackdrop