Feature request: custom branding

[opragel]

It would be lovely to have the ability for additional custom branding in Santa - it's a common request at enterprise businesses and otherwise, often from leadership. Branding can also help with end-user trust that notifications are from trusted software deployed by their organization.

Something like logo support and ability to add an organization name to a line that appears in the notifications (not the notification center ones, the blocking ones) would be sufficient to me personally. Something like 'Managed by OrganizationName' - similar to what Tailscale does. I don't mind if the existing / santa-specific branding remains, just adding our own elsewhere would be sufficient. I think some folks might like that but I don't think it's necessary.

On a lesser note, if custom logo support was added, I think it would be nice to be able to point to a static URL, to something on the local file system, or a base64 encoded image. But as long as there's one option, works for me.