"is the release of a golf club a conscious act or does it happen automatically through a good swing?"
I think the first question you need to ask yourself is what is the release in the golf swing? To answer that we must first define the term release. Assuming Merriam-Webster is a reliable source, the phrase "to let go" is the most applicable portion of the definition when referring to the golf swing. Okay, so what are we letting go of? Certainly not the club... I don't know about you but I try not to let go of my club. I'm sure we could release the club and still hit the ball, but I don't think it would be very efficient or repeatable. I would say we let go of energy. In my opinion there are many releases in the golf swing, only one of which resembles the traditional understanding of a release.
The ultimate release in the golf swing is impact. We strive to let go of as much energy as needed from the club head to the ball while being able to project it to a target. Other releases in the swing involve letting go of the energy in specific components such as the wrist angles or shoulder rotation. When we form those angles or rotate those components and move the club we generate potential energy, reconciling those angles or the rotation converts our potential energy to kinetic energy. Releases can be termed in groups such as releasing ground forces (the potential energy created by downloading multiple components) or Homer Kelley's power package (the four power accumulators and four pressure points). Sorry to get so uber scientific on you but this topic is a big pet peeve of mine.
Now about that traditional release. I like to call that the rapid turning of the forearms and changing of the wrist angles(both up and down as well as side to side). Understand this, if these components change at an excessively high rate coming into impact the face to path relationship becomes very unpredictable making it harder to generate a repetitive ball flight. As the forearms rollover the face de-lofts and closes, the toe of the club turns down, the heel moves out and the toe in, the handle of the golf club actually goes backward, and the path of the center of gravity turns aggressively out to in. That is a lot of things happening at once so I like to call the traditional release chaotic.
If you're looking for advice for what to do with the arms and wrists on the through swing I would say work on getting the arms extended and the lead wrist close to flat at impact. The longer they remain in this position just before and after impact the more predictable the face to path relationship should be.