I think as much as you can, you should keep your nails filed smoothly so they don't catch on the strings. However, I don't think you need to keep them dragonlady long.
I keep the nails on my left hand fairly short because it helps with the fingering, but the nails on the right hand a bit longer. I unfortunately work at a job where my nails break off--so I can't really grow them that long anyway. I try to keep them polished to so they don't split, but if you aren't a girly girl--you can use clear polish or a nail strengthener.
Of course, I'm hardly a serious guitarist (I do play classical and not that well), and I think flamenco guitarists use their nails a bit more because of the stylistic concerns (playing style not fashion style)
On the other hand,, Christopher Parkening--world reknown classical guitarist--files HIS nails to a mere 1/16" to 1/8" edge beyond the flesh of the fingertips. In his books, "The Christopher Parkening Guitar Method, Vol. 1 and Vol. 2)--he details some very precise instructions on how to keep your nails files in the correct shape and condition for playing, but the optimum nail length he prefers is not beyond that one-eighth of an inch.
You can keep an emery board or nail file handy just before you play the guitar to get rid of any ragged edges.
He also mentioned fake fingernails called "players' nails" made just for guitarists (especially if your nails have broken off beyond the quick). I never heard of them before--but there you are. I googled them and found this website.
There are actually several websites that offer advice about nail length for guitarists. I think you might have to experiment until you find the best solution for your playing without having to give up
your parkour. (I know what a tomboy is, but I had to look up "parkour")
I'll list a few below.
Plus a video:
(There should be some on Youtube too)
Most guitarists don't seem to have talons--I'm sure there are exceptions.