It likely got off to a slow start because of the low temperature. If
it is bubbling now, you can wait a few more days before transfer to a
carboy. You won't hurt anything by going to a carboy too soon, in fact
some of my kit wines have become much more active when transferred to
the carboy. What you don't want is to transfer it to a carboy and also
warm it fast, or you may end up either blowing the air lock off, or
having the wine foam over and through the air lock (keep a sulphite
solution in the air lock, which won't hurt the wine, rather than
chloriclean).

If you have bubbling now, you don't need to add yeast. If you are
going to keep it in the primary for a bit longer, you could try to
warm the room up.

For white wines, a slow fermentation is supposed to result in better
flavour, but not necessarily in reds.