New systems in the table within the last 24 hours should be highligted

[sargonas]

As it says, I think I want to add a context highlight for "new" systems in the table of the web ui

[sargonas]

This is now added in #21 but I have a new thing I want to add with this in mind: "System first seen date" on the table entires.

[sargonas]

first seen done with #23 but need to noodle over it a bit during further updates to see how satisfied I am with the look and layout