There is a somewhat major difference between add_string_constant (not static) and push_constant_text (static + constant.:))
But I can agree that the string function names are rather messy. It is a rather big job to change them all to be consistent, however.
On a somewhat related note, I noticed that the string structure no longer has extra padding bytes available, so adding new string types (substring) is not possible without increasing it's size, or decreasing the maximum allowed string length to 2Gb again (or going through all the signed/unsigned work and changing it to at least 4Gb).