Initial commit: ClawdDotNet

Import des bestehenden Projektstands in Git.
- .NET 10 WinForms Anwendung (Multi-Agent / Tool-System)
- .gitignore fuer Build-Artefakte, Secrets und Runtime-Daten ergaenzt

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Directory.Build.targets

@@ -0,0 +1,16 @@
+<Project>
+  <Target Name="StampBuildDate" BeforeTargets="CoreCompile">
+    <PropertyGroup>
+      <_BuildTimestamp>$([System.DateTime]::Now.ToString("yyyy-MM-dd HH:mm:ss"))</_BuildTimestamp>
+      <_BuildTimestampFile>$(IntermediateOutputPath)BuildTimestamp.g.cs</_BuildTimestampFile>
+    </PropertyGroup>
+    <WriteLinesToFile
+      File="$(_BuildTimestampFile)"
+      Lines="[assembly: System.Reflection.AssemblyMetadata(&quot;BuildDate&quot;, &quot;$(_BuildTimestamp)&quot;)]"
+      Overwrite="true"
+      WriteOnlyWhenDifferent="false" />
+    <ItemGroup>
+      <Compile Include="$(_BuildTimestampFile)" />
+    </ItemGroup>
+  </Target>
+</Project>