There's not really anything wrong with having a "13A" socket on a lighting circuit which can't be cured with a clear label on the socket and, if you really want, making the plug difficult to remove by attaching it with tape, cable ties or whatever.Sorry, silly me... It's late If agree apart from anything else it's not obvious to have things done this way, and in general obvious is good!
The regulations explicitly allow a BS1363 (i.e. "13A") socket to be supplied by a lighting circuit.
Kind Regards, John