Query: NZ Visa for Partner of Citizen

Hello everyone, I’ve been in a genuine, stable relationship with my New Zealand partner for over 8 years, and we’ve been living together overseas the entire time. I don’t plan to move to New Zealand permanently for another 4–5 years, but I’m looking for a visa that allows me to enter and exit NZ freely in the meantime, mainly for visits. Which type of visa should I apply for? Thanks in advance!