Add more robust error handling to all the sample build scripts

samples/CSharpUno/build.bat

@@ -12,7 +12,9 @@ set "version=%~1"
 echo.
 echo Compiling CSharpUno with dotnet...
 dotnet publish -c Release --framework net9.0-desktop -o %~dp0UnoSample\publish UnoSample\UnoSample.csproj
+if errorlevel 1 exit /b 1
 
 echo.
 echo Building Velopack Release v%version%
 vpk pack -u CSharpUno -v %version% -o %~dp0UnoSample\releases -p %~dp0UnoSample\publish --mainExe UnoSample.exe
+if errorlevel 1 exit /b 1

samples/CSharpUno/build.sh

@@ -1,4 +1,5 @@
 #!/bin/bash
+set -e
 
 # Check if version parameter is provided
 if [ "$#" -ne 1 ]; then