resolve keyboard shortcuts through one action table instead of a switch

src/ui/BlueprintLibrary.h

@@ -44,6 +44,11 @@ public:
     // (REQ-UI-BLUEPRINT-CREATE).
     bool getCanCaptureSelection() const;
 
+    // True once C has captured something -- the condition under which V does anything
+    // (REQ-UI-BLUEPRINT-TEMP), and so the condition under which the controls panel
+    // offers it (REQ-UI-CONTROLS-ACCURACY).
+    bool getHasTemporaryBlueprint() const;
+
     // Captures the current selection under the given name and appends it to the list.
     // Silently does nothing when nothing player-placeable is selected.
     void saveSelectionAs(const QString& name);