Hello Emacs maintainers,

This patch improves built-in package upgrade checks by adding
package--newer-with-priority-p.  Combines version and priority checks:
1. New numeric version > built-in
2. Priority version > built-in (when enabled)
Replaces direct comparisons in package-menu--find-upgrades.  Uses
package-desc-status instead of array indexes.

Happy to adjust as needed for inclusion in master.

Best regards,
David D.