Add Office 2016 support, bump to v1.20

Office 2016 Standard, Professional Plus, and Home & Business editions
added with PerpetualVL2019 channel for volume licenses.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

InstaSoftOfficeTool.csproj

@@ -9,9 +9,9 @@
     <Company>InstaSoft Zrt.</Company>
     <Product>InstaSoft Office Tool</Product>
     <Copyright>Copyright (c) InstaSoft Zrt. 2026</Copyright>
-    <Version>1.1.9</Version>
+    <Version>1.20</Version>
-    <AssemblyVersion>1.1.9.0</AssemblyVersion>
+    <AssemblyVersion>1.20.0.0</AssemblyVersion>
-    <FileVersion>1.1.9.0</FileVersion>
+    <FileVersion>1.20.0.0</FileVersion>
     <ApplicationManifest>app.manifest</ApplicationManifest>
     <LangVersion>latest</LangVersion>
   </PropertyGroup>

MainWindow.xaml

@@ -45,7 +45,7 @@
                                    Foreground="{StaticResource TextSecondaryBrush}" Margin="0,-2,0,0"/>
                     </StackPanel>
                 </StackPanel>
-                <TextBlock Text="v1.19" HorizontalAlignment="Right" VerticalAlignment="Center"
+                <TextBlock Text="v1.20" HorizontalAlignment="Right" VerticalAlignment="Center"
                            FontSize="12" Foreground="{StaticResource TextSecondaryBrush}"/>
             </Grid>
         </Border>

Models/OfficeEdition.cs

@@ -99,6 +99,35 @@ namespace InstaSoftOfficeTool.Models
                         }
                     };
 
+                case OfficeVersion.Office2016:
+                    return new[]
+                    {
+                        new OfficeEdition
+                        {
+                            DisplayName = "Standard",
+                            Description = "Alapvető irodai alkalmazások: Word, Excel, PowerPoint, Outlook, OneNote",
+                            ProductId = "Standard2016Volume",
+                            Channel = "PerpetualVL2019",
+                            IsVolume = true
+                        },
+                        new OfficeEdition
+                        {
+                            DisplayName = "Professional Plus",
+                            Description = "Teljes csomag: Word, Excel, PowerPoint, Outlook, Access, Publisher, OneNote, Skype for Business",
+                            ProductId = "ProPlus2016Volume",
+                            Channel = "PerpetualVL2019",
+                            IsVolume = true
+                        },
+                        new OfficeEdition
+                        {
+                            DisplayName = "Otthoni és kisvállalati verzió",
+                            Description = "Word, Excel, PowerPoint, Outlook, OneNote — vállalkozásokban is használható",
+                            ProductId = "HomeBusiness2016Retail",
+                            Channel = "Current",
+                            IsVolume = false
+                        }
+                    };
+
                 default:
                     return new OfficeEdition[0];
             }

Models/OfficeVersion.cs

@@ -4,6 +4,7 @@ namespace InstaSoftOfficeTool.Models
     {
         Office2024,
         Office2021,
-        Office2019
+        Office2019,
+        Office2016
     }
 }

Pages/VersionPage.xaml

@@ -42,6 +42,15 @@
                                FontSize="12" Foreground="{StaticResource TextSecondaryBrush}" Margin="0,2,0,0"/>
                 </StackPanel>
             </RadioButton>
+
+            <RadioButton x:Name="Rb2016" Style="{StaticResource CardRadioButton}"
+                         GroupName="Version" Margin="0,0,0,10">
+                <StackPanel Margin="8,2">
+                    <TextBlock Text="Office 2016" FontSize="18" FontWeight="SemiBold"/>
+                    <TextBlock Text="2016. szeptemberi kiadás · Windows 7 / 8.1 / 10 · Támogatás lejárt: 2025.10."
+                               FontSize="12" Foreground="{StaticResource TextSecondaryBrush}" Margin="0,2,0,0"/>
+                </StackPanel>
+            </RadioButton>
         </StackPanel>
     </Grid>
 </Page>

Pages/VersionPage.xaml.cs

@@ -20,6 +20,7 @@ namespace InstaSoftOfficeTool.Pages
                 case OfficeVersion.Office2024: Rb2024.IsChecked = true; break;
                 case OfficeVersion.Office2021: Rb2021.IsChecked = true; break;
                 case OfficeVersion.Office2019: Rb2019.IsChecked = true; break;
+                case OfficeVersion.Office2016: Rb2016.IsChecked = true; break;
             }
         }
 
@@ -28,6 +29,7 @@ namespace InstaSoftOfficeTool.Pages
             if (Rb2024.IsChecked == true) _config.Version = OfficeVersion.Office2024;
             else if (Rb2021.IsChecked == true) _config.Version = OfficeVersion.Office2021;
             else if (Rb2019.IsChecked == true) _config.Version = OfficeVersion.Office2019;
+            else if (Rb2016.IsChecked == true) _config.Version = OfficeVersion.Office2016;
             return true;
         }
     }