Input_boolean read-only on the GUI

[123 (Taras)]

@Octofinger

It shouldn’t be too hard to have a read-only flag

An entity displayed in an Entities card can be made ‘read-only’ in the UI by setting the value of type to simple-entity.

@Octofinger

This way, we don’t have to create read-only entities, as they have to be writable at some point, at least by an automation, but they can be shown read-only in GUI.

A Trigger-based Template Sensor can be made writable via an automation.