Back to the original question, and assuming that you want to go with a smart bulb…
You’re right that a smart bulb needs to always have current or it can’t hear the next on command.
The easiest way to address that is to put an inexpensive switch lock over the existing switch (the one I use cost about two dollars) and then put a battery operated smart switch on the wall next to it. That way there are no wiring requirements, but you still have a switch that looks like a switch and feels like a switch and can be used whenever you want to. You could also get a second one to put right next to your daughter’s bed. Or she could use her phone, whatever you think is better.
Once the Bulb is up with current on you can then dim it from either the phone or automation set up through smart things.
Now it’s just a question of selecting a switch to go on the wall. Which one you pick will depend in part on how often you think it’s going to be used. Here are some ideas: