Detecting failed update with prereq #96

• I have searched the issues of this repository and believe that this is not a duplicate.

Ⅰ. Issue Description

Failed update when a file locked

Ⅱ. Describe what happened

We had issue with update believeing something has been updated and instead it was not.

We should add a check in the update that the file was actually changed runnign the update process

Ⅲ. Describe what you expected to happen

If for some reason a file cannot be updated a warning should be issued.

The prerequisite management check if file exists after the update but the update fails this goes unnoticed.

So we should check more in depth: for example store the size of the file and the last mod and ensure it was changed after the update, otherwise issue a warning.

NOTE there are legitimate case when there is NOT a file associated to an update. It is possible not to have a file - in this case the update is expected to create an empty file to declare the update was performed.

Ⅳ. How to reproduce it (as minimally and precisely as possible)

If you have a running nuv task that makes busy for example bun and you try to update you will end up with the old executable but you believe it was updated

Ⅴ. Anything else we need to know?

Ⅵ. Environment:

• OPS CLI version: 0.1.0-2501041342.dev