[Feat]: Incorporate Image Bloat analysis as an extension

[mikemccracken]

Is your feature request related to a problem? Please describe.

image bloat can occur when files in lower layers are removed or modified.
It's useful to be able to track the amount of data in an image that will not be visible in the final extracted/mounted image, in order to prioritize work on improving builds.

Describe the solution you'd like

when an image is pushed to zot, its layers could be scanned to calculate bloat statistics, and that should be made available via API and zot-ui

Describe alternatives you've considered

No response

Additional context

No response