It's in the middle between the two!

It would be interesting to have an electronic keyboard that watches what you are playing and decides when you press the D-sharp/E-flat key, which note it should play.

Some old style organs that are not "well-tempered" have split keys for some notes, so that you can choose D# vs Eb (for example), depending what else is going on.

I'm sure I've see on here something that does not just that, but also remembers what it just did so when you play your next notes it doesn't jump to a different tuning.

There are also digital keyboards that let you bend pitch after you hit a note by shifting the pressure similar to a violin.

Could also be exactly the same as "the two", as violinists would also often just play those two at the traditional "piano" pitch, when playing alonside a piano and other such instruments.

Sorry but as a guitarist this just sounds like "violinists miss the half-step notes on purpose"

Which is okay. I like to bend notes too, but just call it what it is.

Depends on the temperament you are shooting for, at least that's my understanding after reading the article.