Add missing v24.0.0 changelog entries for #19460 and #19427

[timvaillancourt]

Description

This PR adds missing v24.0.0 changelog entries for #19460 and #19427

For some reason promptless was missed or never suggested changelog/ updates - there were website updates, however

I also added a "Security" topic to MAINTAINERS.md with @timvaillancourt

Details:

• Breaking change: external decompressor no longer read from backup MANIFEST by default
• VTOrc: ordered recovery execution and semi-sync rollout improvements
• Added a "Security" topic to MAINTAINERS.md w/@timvaillancourt

Related Issue(s)

Checklist

• "Backport to:" labels have been added if this change should be back-ported to release branches
• If this change is to be back-ported to previous releases, a justification is included in the PR description
• Tests were added or are not required
• Did the new or modified tests pass consistently locally and on CI?
• Documentation was added or is not required

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