fix: #3629377 Install and configure Klaro instead of relying on the removed drupal_cms_privacy_basic

Issue: https://www.drupal.org/i/3629377 (parent: https://www.drupal.org/project/horizonaid/issues/3629200)

Why: since Drupal CMS 2.2.3 (7 October 2026) a fresh drupal/cms requires drupal/tagify ^2.0.4. Drupal CMS 2.2 removed drupal_cms_admin_ui, drupal_cms_content_type_base, drupal_cms_media and drupal_cms_privacy_basic (drupal.org lists them as replaced by Drupal CMS Basics). Their last releases (2.1.6) require Tagify 1, so the Vardot site templates can no longer be installed from the Drupal CMS installer. Varbase carries the pieces itself instead of switching to Drupal CMS Basics (drupal_cms_site_template_base): applied first, that recipe would take over Varbase's own metatag defaults and the page and media displays (20 configuration items differ).

Change:

• Install Klaro, whose permissions the roles in this recipe already grant, with its settings, the privacy settings ECA model and the "My privacy settings" footer link.
• Keep the YouTube and Vimeo Klaro apps off, as before. Remote videos ask for consent through the ECA model in Varbase Media Base.
• Require drupal/klaro, drupal/eca and drupal/modeler_api.

Tested on DDEV today, with all the related branches together:

• Fresh Drupal CMS 2.2.3 (Tagify 2.0.4): Horizon Aid installs by drush and through the browser installer; Educare, The Rightup and Varbase Starter install by drush. None of the removed drupal_cms recipes is pulled in.
• Varbase base (drupal/varbase_project 11.0.x-dev, Tagify 1.2.54): Horizon Aid installs by drush.
• YAML lint and composer validate pass on every package.

Merge order: the six Varbase recipe MRs first, then the site template MRs.

Related: Varbase Content Base !37, Varbase Editor Base !25, Varbase Media Base !22, Varbase Admin Base !35, Varbase Page Base !14, Educare !82, Horizon Aid !104, The Rightup !77, Varbase Starter !70.

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