feat: export/import JSON des sessions, stats et armurerie via partage systeme

lib/main_navigation_holder.dart

@@ -37,23 +37,27 @@ class _MainNavigationHolderState extends State<MainNavigationHolder> {
   // rafraîchissent pas seuls).
   int _statsTick = 0;
   int _historyTick = 0;
+  int _homeTick = 0;
+  int _garageTick = 0;
 
   void selectTab(int index) {
     if (!mounted) return;
     setState(() {
       _selectedIndex = index;
+      if (index == mainTabHome) _homeTick++;
       if (index == mainTabHistory) _historyTick++;
       if (index == mainTabStats) _statsTick++;
+      if (index == mainTabGarage) _garageTick++;
     });
   }
 
   @override
   Widget build(BuildContext context) {
     final screens = [
-      const HomeScreen(),
+      HomeScreen(refreshTick: _homeTick),
       HistoryScreen(refreshTick: _historyTick),
       StatisticsScreen(refreshTick: _statsTick),
-      const WeaponListScreen(),
+      WeaponListScreen(refreshTick: _garageTick),
     ];
     return Scaffold(
       body: IndexedStack(