Run water from under deck to backyard
What type of wallis the faucet mounted into? I was goingnto recommned a new pipebbut if you said you may break the wall that's a no go. For the winter you shoulsnt have to worry about freezing as long as you shut off the water to the facuet ibside the house and drain out your hose. I belive they do make pvc to copper but ibwould recommend just using copper and putting in inside a piece of pvc for extra protection. I apologise but I don't know anything about drip irrragation however