Nice! I use Umbraco.JsonSchema.Extensions as well, but like this:

xml
    <!-- Updates the version in the umbraco-package.json file to the same version as the NuGet package -->
    <Target Name="UpdateUmbracoPackageJsonVersion" AfterTargets="Build">
        <PropertyGroup>
            <UmbracoPackageJsonPath>$(ProjectDir)wwwroot\App_Plugins\CoreContent\umbraco-package.json</UmbracoPackageJsonPath>
        </PropertyGroup>
        <Message Text="Checking for umbraco-package.json at: $(UmbracoPackageJsonPath)" Importance="High" />
        <JsonPathUpdateValue JsonFile="$(UmbracoPackageJsonPath)" Path="$.version" Value=""$(VersionPrefix)"" Condition="Exists('$(UmbracoPackageJsonPath)')" />
        <Message Text="✅ Updated umbraco-package.json version to $(VersionPrefix)." Importance="High" Condition="Exists('$(UmbracoPackageJsonPath)')" />
        <Message Text="⚠️ Skipped updating umbraco-package.json version - file not found at $(UmbracoPackageJsonPath)." Importance="High" Condition="!Exists('$(UmbracoPackageJsonPath)')" />
    </Target>