Add a ui_read_only option for input_*

The input_text, number, date etc are a nice easy way to display info to the user. These can also be updated using automations. It would be nice if it was possible to set these to read only in the UI so that an automation could update the state of these and the user wasn’t able to change it. This can currently be accomplished with a template sensor on top of the input_* but it would be nice if I didn’t have to create an extra sensor just so it’s not directly editable.

You could do this already with e.g. a markdown card and the lovelace template module.