Not really such a thing. Use a lightweight 3 season tent for 3 seasons...you can usually extend a bit into winter conditions depending on the tent. Get a proper "4 season" tent for winter camping if you actually do that.
The main difference is that light 3 season tents have lots of mesh and venting and will be very drafty and cold in the winter where 4 season tents use much less mesh and venting, are often single walled and will the heavy and stuffy in the summer.
A good 3 season tent to look at is the Big Agnes Copper Spur UL2 which comes in a couple of versions depending how light weight you want to go and how much you want to spend...There are lots of other good options but that one is very highly rated. I had the original version but now use a Big Agnes Tiger Wall UL2 to save 8oz for a bit less robustness and a bit more pitching annoyance. MSR and NEMO have competing tents and the latest crop of REI Quarter Dome tents are worth a look.
There are also so called "trekking pole" tents some of which supposedly can handle weather well if you don't mind having to pitch them but that requires some careful research. They are generally lighter because they use your trekking pole(s) instead of a dedicated pole structure. REI have just starting making these this year and while they look promising there are early reports of that 1 person does not handle condensation well in certain conditions.
For occasional use winter tents, one light weight reasonable cost option is the Black diamond First Light 2P (for some reason REI only stocks the 3P version and for some reason BD only make in it light green...). I have not used this tent personally but it is the one I would choose to try out winter camping.
Note that lightweight 2 person tents are great for extended solo use but a squeeze for 2 people. For a week with 2 people, a 3 person tent will likely be more comfortable.