fix: Windows uyumlulugu - APPDATA config, taskkill

lib/services/window_persistence.dart

@@ -5,8 +5,13 @@ import 'package:flutter/material.dart';
 /// Persists and restores window position and size.
 class WindowPersistence {
   static File get _configFile {
-    final home = Platform.environment['HOME'] ?? '/tmp';
-    return File('$home/.config/imajviewer/window.json');
+    String dir;
+    if (Platform.isWindows) {
+      dir = '${Platform.environment['APPDATA'] ?? Platform.environment['USERPROFILE'] ?? '.'}/imajviewer';
+    } else {
+      dir = '${Platform.environment['HOME'] ?? '/tmp'}/.config/imajviewer';
+    }
+    return File('$dir/window.json');
   }
 
   /// Save window rect synchronously (safe to call before destroy).

lib/shortcuts/app_shortcuts.dart

@@ -21,7 +21,11 @@ class AppShortcuts extends StatelessWidget {
 
           // Ctrl+Shift+Q: tüm pencereleri kapat
           if (ctrl && shift && event.logicalKey == LogicalKeyboardKey.keyQ) {
+            if (Platform.isWindows) {
+              Process.runSync('taskkill', ['/F', '/IM', 'imajviewer.exe']);
+            } else {
               Process.runSync('pkill', ['imajviewer']);
+            }
             return KeyEventResult.handled;
           }