Q) Is the mitzvah of drinking wine on Purim associated with the se’udah – or is it an independent mitzvah?
A) The Rambam (in Hilchos Megilla), when delineating the mitzvoh of se’udoh of Purim rules: “One should eat meat and drink wine… and one should drink wine until he is inebriated and falls asleep.”
It appears from the wording of the Rambam that drinking wine on Purim is in the context of the se’udoh specifically, and is not an independent mitzvoh.
The Shulchan Aruch (OC Siman 695) first discusses se’udas Purim and then, in the following halocho, brings the obligation of “chayev inish livsumei b’purayo…” – the obligation to drink wine/become inebriated on Purim.
It is not conclusive from the Shulchan Aruch if drinking wine on Purim is specifically in the context of the se’udoh – like the Rambam appears to learn, or since the Shulchan Aruch separates between the halochos of se’udo and drinking wine, he opines that they are in fact independent obligations