Meeting code can be interesting.

The landscape lighting set you found most likely has a transformer that plugs into a receptacle and the manufacturer feels they fall under cord and plug connected equipment NEC article 680.7. They have to stay 10' away.

The 2002 NEC 680.22 (B) (4) says no lighting closer than 5' to the pool and from 5' to 10' it must be GFCI protected. It says more but this pertains to what you asked. I feel a landscape lighting system would fall under this if the transformer were to be permanently hardwired and GFCI protected. Some brands of transformer are designed to be either cord and plug connected or hard wired.

You should talk to your local inspector since they have final say.

At least where I am in CA, the lights have to be 5 ft away from the water.

I'll check with the city inspector and the lighting company. Thank you both for your responses.