Include list of scanned images in metrics

[1RandomDev]

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

First of all I'm really not a fan of automatic updates, I need to see which services require an update and later when I have time I'll update and test the affected apps. Since I often miss notifications I've created a custom HomeAssistant sensor that displays the number of available updates from the metrics API, but unfortunately they don't include a list of images I need to update so I still have to check the Watchtower logs every time.

Describe the solution you'd like

Would be really helpful if the metrics would also include a list of outdated images that I could directly display on the dashboard.

Describe alternatives you've considered

Manually checking the Watchtower logs every time I want to update.

Additional context

No response

[github-actions]

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