The Maglite Solitaire is a single mode (47 lumens) AAA light that is off when the head is completely screwed down and turns on when unscrewed. It comes with a split ring and a small lanyard.
I have a random BLF348 that has a keyring hole on it. Not sure if it was actually a BLF348 or a clone but only one arrived with it. Forgot where I bought it though. Based on gearbest there are 2 versions. It’s out of stock though
Yes I have that one too, but the hole is way too small. It’s possible to stuff a ring though it, but the ring would be so thin that it bends with little force and you loose the light very fast. I had a lumintop tool attached with a thicker ring and still lost it because the ring has failed.
Seeknite looks nice, but no keychain attachment thing?
If you should decide the Maglite Solataire (a ‘reverse twisty’) meets your requirements, you would also have the option of the “Spectrum” model which offers warmish hi-CRI.
A couple of years back someone reviewed the Singfire SF-346 which on the surface seems to meet your requirements.
Personally my keychain lights (an old Fenix L0P and an old DQG Tiny) are multi-mode twisties.