Null safety fixes + Plus Records and Medals buttons

Null safety (prevents NullReferenceException crashes):
- RefreshBox: null check on GetBoxSlotAtIndex result
- RefreshParty: null check on GetPartySlotAtIndex result
- PushUndo: guard existing slot before DecryptedBoxData access
- RefreshExtraSlots: null check on slotInfo.Read result
- ExportBoxShowdown: null check in LINQ Where clause
- VerifyAllPkm: null/empty species guard

Missing controls added:
- Plus Records button in Moves tab (IPlusRecord, Gen 8+)
- Medals button in Cosmetic tab (ISuperTrainRegimen, Gen 6)

PKHeX.Avalonia/ViewModels/MainWindowViewModel.cs

@@ -811,7 +811,7 @@ private async Task ExportBoxShowdownAsync()
         try
         {
             var box = SaveFile.GetBoxData(SavEditor.CurrentBox);
-            var text = string.Join("\n\n", box.Where(p => p.Species > 0).Select(ShowdownParsing.GetShowdownText));
+            var text = string.Join("\n\n", box.Where(p => p is not null && p.Species > 0).Select(ShowdownParsing.GetShowdownText));
             if (string.IsNullOrWhiteSpace(text))
             {
                 StatusMessage = "No Pokemon in box to export.";

PKHeX.Avalonia/ViewModels/PKMEditorViewModel.cs

@@ -338,9 +338,13 @@ public string NatureTooltip
     [ObservableProperty] private ComboItem? _selectedAlphaMove;
     [ObservableProperty] private bool _hasAlphaMove;
 
-    // Move Shop / Tech Record visibility
+    // Move Shop / Tech Record / Plus Record visibility
     [ObservableProperty] private bool _hasMoveShop;
     [ObservableProperty] private bool _hasTechRecords;
+    [ObservableProperty] private bool _hasPlusRecord;
+
+    // Super Training (Medals) visibility — Gen 6
+    [ObservableProperty] private bool _hasSuperTraining;
 
     // Gen-specific: Catch Rate (Gen 1)
     [ObservableProperty] private int _catchRate;
@@ -1478,6 +1482,12 @@ public void PopulateFields(PKM pk)
         // Tech Records (Gen 8+)
         HasTechRecords = pk is ITechRecord;
 
+        // Plus Records (Gen 9a - Z:A)
+        HasPlusRecord = pk is IPlusRecord;
+
+        // Super Training / Medals (Gen 6)
+        HasSuperTraining = pk is ISuperTrainRegimen;
+
         // Origin Mark indicator
         var gen = pk.Generation;
         HasOriginMark = gen >= 3;
@@ -1896,6 +1906,39 @@ private async Task OpenTechRecords()
         catch (Exception ex) { LegalityReport = $"Tech Record error: {ex.Message}"; }
     }
 
+    [RelayCommand]
+    private async Task OpenPlusRecord()
+    {
+        if (Entity is not IPlusRecord plus) return;
+        if (Entity.PersonalInfo is not IPermitPlus permit) return;
+        try
+        {
+            PreparePKM();
+            var vm = new PlusRecordEditorViewModel(plus, permit, Entity);
+            var view = new PlusRecordEditorView { DataContext = vm };
+            var mainWindow = (Application.Current?.ApplicationLifetime as IClassicDesktopStyleApplicationLifetime)?.MainWindow;
+            if (mainWindow != null)
+                await view.ShowDialog(mainWindow);
+        }
+        catch (Exception ex) { LegalityReport = $"Plus Record error: {ex.Message}"; }
+    }
+
+    [RelayCommand]
+    private async Task OpenMedals()
+    {
+        if (Entity is not ISuperTrainRegimen st) return;
+        try
+        {
+            PreparePKM();
+            var vm = new SuperTrainingEditorViewModel(st);
+            var view = new SuperTrainingEditorView { DataContext = vm };
+            var mainWindow = (Application.Current?.ApplicationLifetime as IClassicDesktopStyleApplicationLifetime)?.MainWindow;
+            if (mainWindow != null)
+                await view.ShowDialog(mainWindow);
+        }
+        catch (Exception ex) { LegalityReport = $"Super Training error: {ex.Message}"; }
+    }
+
     // --- Ribbons / Memories commands ---
 
     [RelayCommand]

PKHeX.Avalonia/ViewModels/SAVEditorViewModel.cs

@@ -287,6 +287,7 @@ private void RefreshBox()
         for (int i = 0; i < slotCount && i < BoxSlots.Count; i++)
         {
             var pk = _sav.GetBoxSlotAtIndex(CurrentBox, i);
+            if (pk is null) continue;
             BoxSlots[i].Entity = pk;
             if (pk.Species == 0)
             {
@@ -310,6 +311,7 @@ private void RefreshParty()
         for (int i = 0; i < _sav.PartyCount && i < PartySlots.Count; i++)
         {
             var pk = _sav.GetPartySlotAtIndex(i);
+            if (pk is null) continue;
             PartySlots[i].Entity = pk;
             if (pk.Species == 0)
             {
@@ -388,7 +390,8 @@ private void SetSlot(SlotModel? slot)
         if (boxIndex >= 0)
         {
             var existing = _sav.GetBoxSlotAtIndex(CurrentBox, boxIndex);
-            PushUndo(CurrentBox, boxIndex, existing, isParty: false);
+            if (existing is not null)
+                PushUndo(CurrentBox, boxIndex, existing, isParty: false);
             _sav.SetBoxSlotAtIndex(pk, CurrentBox, boxIndex);
             RefreshBox();
             return;
@@ -398,7 +401,8 @@ private void SetSlot(SlotModel? slot)
         if (partyIndex >= 0)
         {
             var existing = _sav.GetPartySlotAtIndex(partyIndex);
-            PushUndo(0, partyIndex, existing, isParty: true);
+            if (existing is not null)
+                PushUndo(0, partyIndex, existing, isParty: true);
             _sav.SetPartySlotAtIndex(pk, partyIndex);
             RefreshParty();
         }
@@ -426,7 +430,8 @@ private void DeleteSlot(SlotModel? slot)
         if (boxIndex >= 0)
         {
             var existing = _sav.GetBoxSlotAtIndex(CurrentBox, boxIndex);
-            PushUndo(CurrentBox, boxIndex, existing, isParty: false);
+            if (existing is not null)
+                PushUndo(CurrentBox, boxIndex, existing, isParty: false);
             _sav.SetBoxSlotAtIndex(_sav.BlankPKM, CurrentBox, boxIndex);
             RefreshBox();
             return;
@@ -436,7 +441,8 @@ private void DeleteSlot(SlotModel? slot)
         if (partyIndex >= 0)
         {
             var existing = _sav.GetPartySlotAtIndex(partyIndex);
-            PushUndo(0, partyIndex, existing, isParty: true);
+            if (existing is not null)
+                PushUndo(0, partyIndex, existing, isParty: true);
             _sav.DeletePartySlot(partyIndex);
             RefreshParty();
         }
@@ -524,6 +530,7 @@ private void RefreshExtraSlots(SaveFile sav)
             foreach (var slotInfo in extras)
             {
                 var pk = slotInfo.Read(sav);
+                if (pk is null) continue;
                 var model = new SlotModel
                 {
                     Slot = slotInfo.Slot,
@@ -675,7 +682,7 @@ private void VerifyAllPkm()
                 for (int slot = 0; slot < _sav.BoxSlotCount; slot++)
                 {
                     var pk = _sav.GetBoxSlotAtIndex(box, slot);
-                    if (pk.Species == 0) continue;
+                    if (pk is null || pk.Species == 0) continue;
                     total++;
                     var la = new LegalityAnalysis(pk);
                     if (la.Valid) legal++; else illegal++;

PKHeX.Avalonia/Views/PKMEditorView.axaml

@@ -523,12 +523,14 @@
                                   DisplayMemberBinding="{Binding Text, DataType=core:ComboItem}" Height="25" Width="200" HorizontalAlignment="Left" />
                     </StackPanel>
 
-                    <!-- Move Shop / Tech Records buttons -->
+                    <!-- Move Shop / Tech Records / Plus Records buttons -->
                     <StackPanel Orientation="Horizontal" Spacing="4" Margin="0,4,0,0">
                         <Button Content="Move Shop" Command="{Binding OpenMoveShopCommand}" Padding="6,2" FontSize="10"
                                 IsVisible="{Binding HasMoveShop}" />
                         <Button Content="Tech Records" Command="{Binding OpenTechRecordsCommand}" Padding="6,2" FontSize="10"
                                 IsVisible="{Binding HasTechRecords}" />
+                        <Button Content="Plus Records" Command="{Binding OpenPlusRecordCommand}" Padding="6,2" FontSize="10"
+                                IsVisible="{Binding HasPlusRecord}" />
                     </StackPanel>
 
                     <!-- Relearn Moves -->
@@ -683,10 +685,12 @@
                             </Grid>
                         </StackPanel>
 
-                        <!-- Ribbons / Memories buttons -->
+                        <!-- Ribbons / Memories / Medals buttons -->
                         <StackPanel Orientation="Horizontal" Spacing="4" Margin="0,8,0,0">
                             <Button Content="Ribbons" Command="{Binding OpenRibbonsCommand}" Padding="6,2" FontSize="10" />
                             <Button Content="Memories" Command="{Binding OpenMemoriesCommand}" Padding="6,2" FontSize="10" />
+                            <Button Content="Medals" Command="{Binding OpenMedalsCommand}" Padding="6,2" FontSize="10"
+                                    IsVisible="{Binding HasSuperTraining}" />
                         </StackPanel>
 
                     </StackPanel>