Add Windows keystroke transformation support

Enhance KCEventTransformer to include a method for transforming keystrokes to their Windows equivalents. Update KCDefaultVisualizer to display both macOS and Windows keystroke representations when applicable.

keycastr/KCDefaultVisualizer.m

@@ -33,6 +33,7 @@
 #import "KCDefaultVisualizer.h"
 #import "KCKeystroke.h"
 #import "KCMouseEvent.h"
+#import "KCEventTransformer.h"
 #import "NSBezierPath+RoundedRect.h"
 #import "NSUserDefaults+Utility.h"
 
@@ -316,7 +317,17 @@ static NSRect KC_defaultFrame(void) {
         [self abandonCurrentBezelView];
     }
 
-    [self appendString:[keystroke convertToString]];
+    NSString *macString = [keystroke convertToString];
+    NSString *winString = [[KCEventTransformer currentTransformer] transformedValueForWindows:keystroke];
+
+    NSString *displayString;
+    if (winString.length > 0) {
+        displayString = [NSString stringWithFormat:@"%@  |  %@", macString, winString];
+    } else {
+        displayString = macString;
+    }
+
+    [self appendString:displayString];
 }
 
 - (void)appendString:(NSString *)string

keycastr/KCEventTransformer.h

@@ -41,4 +41,6 @@
 
 - (id)transformedValue:(KCKeycastrEvent *)event;
 
+- (NSString *)transformedValueForWindows:(KCKeycastrEvent *)event;
+
 @end

keycastr/KCEventTransformer.m

@@ -322,6 +322,55 @@ static NSString* kLeftTabString = @"\xe2\x87\xa4";
 	return mutableResponse;
 }
 
+- (NSString *)transformedValueForWindows:(KCKeycastrEvent *)event {
+    if (![event isKindOfClass:[KCKeystroke class]]) {
+        return nil;
+    }
+    
+    KCKeystroke *keystroke = (KCKeystroke *)event;
+    NSEventModifierFlags modifiers = event.modifierFlags;
+    
+    BOOL isCommand = (modifiers & NSEventModifierFlagCommand) != 0;
+    BOOL isControl = (modifiers & NSEventModifierFlagControl) != 0;
+    BOOL isOption = (modifiers & NSEventModifierFlagOption) != 0;
+    BOOL isShift = (modifiers & NSEventModifierFlagShift) != 0;
+    
+    // Only show Windows equivalent if there are modifiers (Command, Control, or Option)
+    // We treat Shift-only as a "simple letter" case usually, unless it's a special key?
+    // User said: "don't duplicate simple letters like 'a | a'".
+    // Shift+A -> "A". Windows: "Shift+A"? Or just "A"?
+    // Usually Windows shortcuts are Ctrl+C.
+    // Let's require Command, Control, or Option for now.
+    if (!isCommand && !isControl && !isOption) {
+        return nil;
+    }
+
+    NSMutableArray *parts = [NSMutableArray array];
+    
+    if (isControl) [parts addObject:@"Win"];
+    if (isCommand) [parts addObject:@"Ctrl"];
+    if (isOption) [parts addObject:@"Alt"];
+    if (isShift) [parts addObject:@"Shift"];
+    
+    // Get the character key
+    NSString *charString = nil;
+    NSString *specialKeyString = [[self _specialKeys] objectForKey:@(keystroke.keyCode)];
+    if (specialKeyString) {
+        // We might want to map some symbols to text if possible, but keeping them as is for now is safer
+        // unless we have a map for Windows names.
+        // For example, arrow keys are symbols in _specialKeys.
+        charString = specialKeyString;
+    } else {
+        charString = [self translatedCharacterForKeystroke:keystroke];
+    }
+    
+    if (charString.length > 0) {
+        [parts addObject:[charString uppercaseString]];
+    }
+    
+    return [parts componentsJoinedByString:@"+"];
+}
+
 - (NSString *)translatedCharacterForKeystroke:(KCKeystroke *)keystroke {
     if ([self shouldReturnOriginalCharactersForKeyCode:keystroke.keyCode 
                                             characters:keystroke.characters] && keystroke.isCommand) {