Add app icon, product name/version, and document them

- New app.ico (from the Cevolani favicon, background made transparent and
  cropped tighter to the logo so it stays legible at 16/24px), wired up via
  ApplicationIcon in the csproj and re-read at runtime for the window icon.
- Named the product "Cevolani StepPrep" and set Version=0.1.0 in the csproj;
  shown in the window title. The CadSearchGui folder/namespace/csproj keep
  their technical name, only the product-facing name changed.
- Updated CLAUDE.md, README.md and docs/architettura.md to reflect the
  product name/version, UiStile.cs, app.ico, and that this app is a
  pre-process step ahead of Creo Distributed Batch.

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

CadSearchGui/CadSearchGui.csproj

@@ -7,6 +7,11 @@
     <UseWindowsForms>true</UseWindowsForms>
     <ImplicitUsings>enable</ImplicitUsings>
     <ApplicationHighDpiMode>PerMonitorV2</ApplicationHighDpiMode>
+    <ApplicationIcon>app.ico</ApplicationIcon>
+    <AssemblyTitle>Cevolani StepPrep</AssemblyTitle>
+    <Product>Cevolani StepPrep</Product>
+    <Company>Cevolani</Company>
+    <Version>0.1.0</Version>
   </PropertyGroup>
 
   <ItemGroup>