Fix CI and release for C# native app

[enaboapps]

Summary

• run CI package scripts directly under PowerShell without nested shell calls
• verify the full Windows package in the release workflow before updater metadata verification

Closes #287.

Validation

• dotnet restore src/SwitchifyPc.sln
• dotnet build src/SwitchifyPc.sln -c Release --no-restore
• dotnet test src/SwitchifyPc.sln -c Release --no-build
• powershell -NoProfile -ExecutionPolicy Bypass -File scripts\Package-Windows.ps1 -StageOnly -SkipSign
• powershell -NoProfile -ExecutionPolicy Bypass -File scripts\Verify-DotnetPackage.ps1
• rg -n --hidden npm|package.json|package-lock|node_modules|\.cjs|electron|Electron|electron-builder|electron-vite|vitest|vite|react|dist-dotnet . -g !.git/** -g !dist/** -g !src/**/bin/** -g !src/**/obj/**