Turkish alley names: Sokak vs Sokağı - Cadde vs Caddesi

I am currently visiting Istanbul and am confused a bit with capturing alley names. On the signs it always says “Sokağı”, but in OSM the name is most times just captured as “Sokak” (or even worse with the abbreviation “Sk.”).

I don’t speak Turkish, but from what I understand “Sokağı” is a form of “Sokak” denoting belonging to something.

What is the consensus on which name to enter into OSM then? I am currently following the “on the ground” rule and add what is on the street sign.

sokağı. accusative singular of sokak
So form should depend on another words in a name