dismiss a dialog with Q, and refuse to dismiss the drop dialog

Three dialogs take Q as a second way out beside Escape: the recipe/schematic
selection dialog and the blueprint selection dialog close outright, and the
layout configuration dialog steps out one level per press -- the module being
placed, then remove mode, then the session. Both of those mode exits now go
through the handler the Remove button uses, extracted from a lambda into
onRemoveButtonClicked(), so the key and the button cannot leave different
state behind.

The schematic choice dialog goes the other way and declines reject(). It had
no close button but Escape still closed it, and the caller then applied
choiceIndex 0 -- awarding whichever option happened to be first. Refusing
reject() covers Escape, Alt+F4, and the window manager together, since all
three funnel through it. It is also the only dialog whose dismissal would
strand state: the poll that opened it does not reopen it while the choices
stay pending, so a drop dismissed is a drop lost.

The key itself is spelled once in DialogDismiss.h rather than in three key
handlers. It stays out of the ControlAction table on purpose: that table
answers what an input does in the player's current situation, and a dialog
has none -- it holds focus and takes the key whatever the world is doing.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ne3mejABZoLWKLh8fgpM3x

src/ui/SchematicChoiceDialog.h

@@ -10,6 +10,9 @@ struct RecipesConfig;
 class BuildingIconCache;
 class ItemIconCache;
 
+// The drop's choice dialog (REQ-DEF-SCHEMATIC-DROP). Unlike every other dialog it
+// cannot be dismissed: clicking an option is the only way out, so getChosenIndex()
+// always names an option the player picked, and exec() only ever returns Accepted.
 class SchematicChoiceDialog : public QDialog
 {
     Q_OBJECT
@@ -24,6 +27,14 @@ public:
 
     int getChosenIndex() const;
 
+public slots:
+    // Refuses the dismissal (REQ-DEF-SCHEMATIC-DROP): the drop is a reward the player
+    // has earned, and leaving without choosing would either forfeit it or award the
+    // option that happens to be first. Escape, Alt+F4, and the window manager's close
+    // all funnel through QDialog::reject(), so declining it here turns away every one of
+    // them at once rather than swallowing keys one at a time.
+    void reject() override;
+
 private:
     void onOptionClicked(int index);