OMG, that's SUPER helpful! I do have some follow-up questions, actually!

I select a bulb with pins (instead of a bayonet base) that allows me to directly solder wires to it.

So maybe I'm not putting in the right search terms because when I do "12vdc led bulbs pins warm white dimmable" and search, I get mostly halogen two prong bulbs. BUT that got me thinking... Why don't I use those, because those are already set for 110V? I found these, let's say I pair those with these sockets, then I guess I wouldn't even need to do the 110/220VAC>12VDC adapter... right?

In this configuration, I guess I would then just splice them together and then connect them to the ceiling. The only thing I'd still have to figure out is where my ground wire goes that comes out of the ceiling given that I would only have a pos and neg wire from the halogen bulb connections...

So I guess now my question is a) does that sound right and maybe simpler than the 12V route? or b) any tips on how I can find those DC12V led bulbs you mentioned? Sorry! Just probably not searching for the right things.

Again, so grateful for the detailed explanation and advice!