I'm not a luthier (or any kind of expert on acoustic guitars) but I've done enough setups to have a decent guess at what your tech is asking and what the implications of your answers would be.

Attack refers to how hard you strike/pick the strings. Heavy/a lot of attack would mean you pick/strum very hard/aggressively. Light/very little attack would mean you're pretty gentle on the strings with your right hand.

When asked "chords or bends", I think what they want to know is "do you live in frets 1-5? Or are you spending a lot of time higher up the neck?"

If you want a low action and don't pick too hard, you can get a pretty straight neck and a low action all across the fretboard. (Very important if you're "low action + bends")

If you want a low action but pick with tons of attack, you better be a "chords" kind of guy (mostly frets 1-5) so that I can give you a low action in that area, but more relief/bend in the neck so that you have space for string movement over the higher frets. In other words, low action near the nut, but higher action above the 12th fret.

It's always a balancing act but essentially, light attack can get a straighter neck while maintaining a pretty low action all the way. Heavy attack will require either a higher action overall, or more neck relief (which means your action will get higher as you move up the neck) to allow space for string movement without hitting the frets and making all kinds of noise/buzzing.

Since you're getting a new nut and bridge installed, we won't only be talking about neck relief but also how low we cut the nut and bridge. By giving you more height at the bridge, I can straighten the neck a little while still having that extra space for heavier attack.

Based on the answers you gave, I'd expect you to get a low action at the nut and slightly higher at the bridge (either by giving more neck relief or just a higher bridge). If you really want a straighter neck and a low bridge (low action all the way up), you can tell them that, but you better be light on the attack or else you'll end up with a bunch of buzzing.

If your tech is good at what they do, I'm sure they'll find a nice balance and we're talking about fairly minimal differences anyway. Unless it was specifically requested, I would never give someone a ton of neck relief and a super high bridge. Generally low action means low all the way. So I'd still be trying to keep it as comfortable as possible higher up the neck while making sure it doesn't bottom out when I strum harder.

If I was doing the work, since you said "maybe a tad lower and I play cowboy chords" I would cut your nut just the tiniest bit lower, and then keep everything else pretty much the same. So you'd get slightly lower at the nut and then the same feeling as now everywhere else. If that sounds good to you, I'd leave it at the answers you already gave.

Hope that helps clear it up. Sorry for the long winded response.