Fix keyboard input recognition for special keys and cross-platform modifiers

- Add explicit handling for backspace, delete, escape, and space keys
- Fix modifier key mappings to work correctly on Linux/Windows (Ctrl key was incorrectly mapped to 'cmd')
- Add platform detection for proper modifier key handling across macOS, Linux, and Windows

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

MSMD_multiLevel.py

@@ -108,6 +108,14 @@ class GraphicsView(QGraphicsView):
                 textFromCode = 'enter'
             elif code == 16777217:
                 textFromCode = 'tab'
+            elif code == 16777219:
+                textFromCode = 'backspace'
+            elif code == 16777223:
+                textFromCode = 'delete'
+            elif code == 16777216:
+                textFromCode = 'esc'
+            elif code == 32:
+                textFromCode = 'space'
             else:
                 textFromCode = chr(code)
         except :
@@ -130,9 +138,15 @@ class GraphicsView(QGraphicsView):
         if(pressedModifiers & Qt.AltModifier):
             modifierTextList.append('alt')
         if(pressedModifiers & Qt.ControlModifier):
+            if sys.platform == 'darwin':  # macOS
                 modifierTextList.append('cmd')  # on the mac this is the command key
+            else:  # Linux and Windows
+                modifierTextList.append('ctrl')
         if(pressedModifiers & Qt.MetaModifier):
-            modifierTextList.append('ctrl')# on the mac this is the control key
+            if sys.platform == 'darwin':  # macOS
+                modifierTextList.append('ctrl')  # on the mac this is the control key
+            else:  # Linux and Windows
+                modifierTextList.append('win')
 
         return modifierTextList
     
@@ -629,11 +643,15 @@ class App(QWidget):
         if(pressedModifiers & Qt.AltModifier):
             modifierTextList.append('alt')
         if(pressedModifiers & Qt.ControlModifier):
-            #modifierTextList.append('ctrl')
+            if sys.platform == 'darwin':  # macOS
                 modifierTextList.append('cmd')  # on the mac this is the command key
+            else:  # Linux and Windows
+                modifierTextList.append('ctrl')
         if(pressedModifiers & Qt.MetaModifier):
-            modifierTextList.append('ctrl')# on the mac this is the control key
+            if sys.platform == 'darwin':  # macOS
-            #modifierTextList.append('win')
+                modifierTextList.append('ctrl')  # on the mac this is the control key
+            else:  # Linux and Windows
+                modifierTextList.append('win')
         return set(modifierTextList) == set(self.currentInputModifiers)
     
     def simplifyModifierList(self, modifierList):