I know that while, for many instruments, enharmonic notes are a single pitch and their differences are more of an interpretation, helping music to remain consistent (it would make more sense for a scale to have C and D♭ than it would to have C and C♯), there are certain instruments that can cover a more-continuous, less-discrete range of pitches. The violin is one such example and while a majority of music written for the violin still treats enharmonic notes as the same pitch, there is music where a distinction between E♯ and F exists (I believe that E♯ is slightly higher than F by an interval called Pythagorean comma).
I want to develop the kind of intonation for this on my violin but I'm not entirely sure how. When I practice intonation, I reference an electric tuner, as sadly, I didn't start playing music until adulthood and missed the window of opportunity for absolute pitch. This works fine for most notes but it doesn't work for enharmonic ones; I've looked all over the place and I haven't found a single tuner that distinguishes between enharmonic notes (I'm not even sure such a thing exists). How do violinists get this kind of intonation?
Addendum: I recently spoke with a violin teacher about this. According to her, because the Pythagorean comma is so small, it has no real practical use in music that is physically played by a person. It's used in 'conceptual' and 'abstract' stuff like the math behind different tuning systems.
Apparently I had misinterpreted information like 'violinists can play B♯ and C as individual notes;' I had thought 'can' in this context referred to a skilled violinist having the capacity to intentionally play them individually, while the word 'can' was actually referring to it technically being possible, as violins have a non-discrete gradient of pitches. While a well ear-trained violinist could carefully make adjustments to their finger positions (more or less a slight shift in the muscles) to get the particular pitch, it's virtually impossible for a person to develop their intonation the point of reliably playing a Pythagorean comma simply because of human error.
She also went on to say that the smallest interval I'd ever really need to learn is a quarter tone (half a semitone) and that's more just if I was interested in certain types of Middle Eastern music.