[Feature] Navigation, Color, Entities on Screensaver

[onyxkyr]

Hello,

I had the opportunity to test out your native lovelace approach - I am really loving it, the responsiveness is amazing and makes the NSPanels much easier to interact with. I have six NSPanels installed currently running the appdaemon version, and for me a couple of features are missing before I can move all panels to the native port. I added two images from the appdaemon version to highlight the following features:

• [ ] Screensaver entities On the bottom right, instead of a weather forecast I have a forecast for the next waste collection, for which I included a custom entity which features waste type as name and corresponding icon.
• [ ] Entity color Expanding on that, the icon is colored depending on how many days remain to the next recycling cycle.

To realise this natively, I would just need to be able to add entities to the screensaver and set their color.

• [ ] Navigation entities In order to control multiple rooms, I set up custom navigation for which I require the navigations in the top right and left corner of the screen (the little house and checkmark, respectively). Being able to set these up would enable easy navigation between different screens.
• [ ] Display timer The appdaemon port features a time for the display. Since we can already toggle the screen via esphome, this would just be nice to have.

I am a little busy in the next weeks, but can also look into helping realise these feature thereafter - haven't found the time to test the new upload mentioned in #20 yet.

Thanks for all your effort!