Add CadSearchGui: WinForms app to index and search the CAD archive

Indicizza le cartelle __Accessori, __B.end, __Corpi, __Fondi in un DB
SQLite locale ed espone una GUI di ricerca (codice, tipo, cartella,
solo ultima versione) con aggiornamento incrementale dell'indice e
stima del tempo rimanente.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

CadSearchGui/CadSearchGui.csproj

@@ -0,0 +1,15 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>WinExe</OutputType>
+    <TargetFramework>net10.0-windows</TargetFramework>
+    <Nullable>enable</Nullable>
+    <UseWindowsForms>true</UseWindowsForms>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Data.Sqlite" Version="10.0.12" />
+  </ItemGroup>
+
+</Project>