I keep a extending mechanic's magnet handy alllllll the time for just such emergencies...
My gut reaction is to listen very carefully after I've dropped something like this.... often times you can hear it bounce and ricochet.
Well... in such cases I recommend a bright flashlight with a narrow/focused beam.
I dip all the nuts and bolts in powdered sugar before I start working so if I drop one I can call the dog over to find it for me.
That's great if it's not stainless steel which is non magnectic.Fwiw, those long bar shaped $4 magnets for holding wrenches work great for sweepingvfor dropped/list fasteners. I put a pieces of thin tape over the magnet to make it easier to clean off.
https://m.harborfreight.com/18-in-magnetic-tool-holder-60433.html?utm_referrer=direct/not provided