[Task] Publishing Queue: promote Beta portlet to primary and rename Dojo portlet to Legacy

Description

The Angular rewrite of the Publishing Queue portlet is currently registered as a separate Beta portlet (publishing-queue-beta, display name Publishing Queue (Beta)) that admins can opt into from the "Add Portlet" picker under Tools. It is not part of any default layout, so end users continue to see the existing Dojo Publishing Queue portlet.

Once the Beta portlet has been validated in production and product sign-off is in place, promote the Angular build to the primary publishing-queue id and rename the Dojo portlet to publishing-queue-legacy so it remains reachable while being clearly labeled as the deprecated implementation.

This swap is intentionally scheduled as a separate ticket so the Beta portlet can bake behind an opt-in install before it becomes the default for every dotCMS user.

Acceptance Criteria

• dotCMS/src/main/webapp/WEB-INF/portlet.xml: rename the Angular <portlet-name>publishing-queue-beta</portlet-name> entry back to publishing-queue, display name Publishing Queue. Rename the Dojo entry from publishing-queue to publishing-queue-legacy, display name Publishing Queue Legacy.
• dotCMS/src/main/webapp/WEB-INF/messages/Language.properties: replace the publishing-queue-beta title key with com.dotcms.repackage.javax.portlet.title.publishing-queue-legacy=Publishing Queue Legacy. The existing publishing-queue=Publishing Queue key stays and now labels the Angular portlet.
• core-web/apps/dotcms-ui/src/app/app.routes.ts: Angular route path changes from publishing-queue-beta back to publishing-queue.
• dotCMS/src/test/java/com/dotmarketing/business/portal/SerializationHelperTest.java: assertion updated from publishing-queue-beta to publishing-queue-legacy; the total portlet count assertion is unchanged.
• Data migration (UpgradeTask): existing customer layouts that reference the old Dojo publishing-queue portletId should continue to render a working portlet after upgrade — either by promoting them to the Angular portlet at the same id, or by rewriting the layout row to publishing-queue-legacy. A documented rollback path is required.
• The Angular portlet is added to the default Publishing / Tools layout so it appears in the menu out of the box for new and upgraded installs. The Legacy portlet remains available in the "Add Portlet" picker but is not in any default layout.
• Product sign-off is recorded in this ticket before the swap PR is merged.

Priority

Medium

Additional Context

Refs #36040 for the original Angular implementation of the portlet. That ticket delivers the Beta portlet; this ticket delivers the promotion to primary once approval is obtained.