Clear active state on arrow count switch and simplify dialog

- Adds _disarmActiveState() to clear selection and retract keypad after mode switch
- Simplifies 'Keep scores?' dialog to just title and Yes/No buttons
- Prevents confusing active end highlighting after rule changes

Note: Hardcoded strings identified for future localization setup

🤖 Generated with [Claude Code](https://claude.ai/code)

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

lib/presentation/pages/scoring_page.dart

@@ -88,20 +88,15 @@ class _ScoringPageState extends State<ScoringPage> with SingleTickerProviderStat
         context: context,
         builder: (BuildContext context) {
           return AlertDialog(
-            title: const Text('Keep current scores?'),
-            content: const Text(
-              'You have existing scores on the scorecard. Do you want to keep them when switching arrow count modes?\n\n'
-              '• Yes: Existing scores will be preserved\n'
-              '• No: All scores will be cleared',
-            ),
+            title: const Text('Keep scores?'),
             actions: [
               TextButton(
                 onPressed: () => Navigator.of(context).pop(false),
-                child: const Text('No - Clear scores'),
+                child: const Text('No'),
               ),
               TextButton(
                 onPressed: () => Navigator.of(context).pop(true),
-                child: const Text('Yes - Keep scores'),
+                child: const Text('Yes'),
               ),
             ],
           );
@@ -127,6 +122,9 @@ class _ScoringPageState extends State<ScoringPage> with SingleTickerProviderStat
           _initializeScores();
         }
         
+        // Clear active state and retract keypad
+        _disarmActiveState();
+        
         // Notify parent of changes
         widget.onArrowsPerEndChanged(arrows);
         widget.onScoresUpdated(scores);
@@ -139,6 +137,9 @@ class _ScoringPageState extends State<ScoringPage> with SingleTickerProviderStat
         endsPerSet = arrows == 3 ? 10 : 6;
         _initializeScores();
         
+        // Clear active state and retract keypad
+        _disarmActiveState();
+        
         // Notify parent of changes
         widget.onArrowsPerEndChanged(arrows);
         widget.onScoresUpdated(scores);
@@ -281,6 +282,16 @@ class _ScoringPageState extends State<ScoringPage> with SingleTickerProviderStat
     });
   }
 
+  void _disarmActiveState() {
+    if (isKeypadVisible) {
+      _animationController.reverse();
+    }
+    isKeypadVisible = false;
+    activeEndIndex = null;
+    selectedRow = -1;
+    selectedColumn = -1;
+  }
+
   void _onBackgroundTapped() {
     if (isKeypadVisible) {
       _animationController.reverse().then((_) {