Editable input_datetime tile (time picker)

Right now input_datetime can only be shown in the top bar (it's in HEADER_ONLY_DOMAINS), so it can't be a tile and can't be changed from the screen.

Use case: I have input_datetime.despertador_hora (time only) that drives my wake-up automation. I'd like to set it from the panel next to the bed instead of opening the HA app.

Proposal:

• Allow input_datetime as a tile, showing its value (07:30, or the date if has_date).
• Tap opens a card with a time picker (hour/minute rollers or − / + steppers, minute step configurable e.g. 1/5/15) that calls input_datetime.set_datetime.
• For has_date: true, a simple date picker as well.