Ability to deactivate (not delete) changelog entries — with reactivate/duplicate option

Description: Currently, changelog entries can only be deleted, not deactivated. Customers who publish time-sensitive notifications (e.g. deployment/downtime notices) need a way to disable an entry without permanently losing it, and to bring it back or reuse its content for future releases. Problem: When a changelog notification is only meant to be live temporarily (for example, a downtime notice created shortly before a deployment and taken down right after), the only option today is to delete it — which erases the entry's history and content entirely. This means that for every recurring notification (e.g. each new deployment), the user has to recreate the changelog entry completely from scratch, with no way to reactivate the previous one or copy over its text. Benefit: Adding a "deactivate/reactivate" state for changelog entries (separate from delete) — or at minimum, a "duplicate/copy text" option — would let customers reuse recurring announcements instead of rebuilding them each time. This saves time for teams that publish repeated, temporary notifications, preserves changelog history, and reduces the risk of inconsistent messaging across releases.