v1.06 — Fix product key paste across all 5 fields

- Use DataObject.Pasting handler to intercept paste before MaxLength truncation
- Full key paste (e.g. XXXXX-XXXXX-XXXXX-XXXXX-XXXXX) distributes across all boxes
- Works when pasting into any of the 5 fields

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>1.0.5</Version>
-    <AssemblyVersion>1.0.5.0</AssemblyVersion>
-    <FileVersion>1.0.5.0</FileVersion>
+    <Version>1.0.6</Version>
+    <AssemblyVersion>1.0.6.0</AssemblyVersion>
+    <FileVersion>1.0.6.0</FileVersion>
     <ApplicationManifest>app.manifest</ApplicationManifest>
     <LangVersion>latest</LangVersion>
   </PropertyGroup>