GHSA-cvxj-4745-843x Content-Security-Policy protection for user content disabled by Jenkins ScreenRecorder Plugin

• Maven io.jenkins.plugins:screenrecorder: <= 0.7 (no fix yet)

Jenkins sets the `Content-Security-Policy` header to static files served by Jenkins (specifically `DirectoryBrowserSupport`), such as workspaces, `/userContent`, or archived artifacts, unless a Resource Root URL is specified. ScreenRecorder Plugin 0.7 and earlier programmatically updates the Java system property allowing administrators to customize the `Content-Security-Policy` header for static files served by Jenkins to include `media-src: 'self'`. On a Jenkins instance with default configuration, this effectively disables all other directives in the default rule set, including `script-src`. This allows cross-site scripting (XSS) attacks by users with the ability to control files in workspaces, archived artifacts, etc. Jenkins instances with Resource Root URL configured are unaffected.