How do you clean the inside?

Warm water and a soft bottle brush usually do the trick. Add a drop of mild washing liquid for stubborn marks. Avoid boiling water. Old glass struggles with sudden temperature changes and might crack.

Can I use it for wine?

Yes, they work well for wine. The wide bowl allows the liquid to breathe before serving. Just remember they lack stoppers.

I'm looking at one with a very rough circular mark on the bottom, does this mean it was broken and ground down?

That rough patch is the pontil mark, a standard feature of hand-blown glass. It shows where the glassblower detached the iron rod after shaping the vessel. Some makers polished this mark smooth, especially on expensive cut crystal. A rough, snapped pontil usually points to an earlier or less formal piece of glass.

I see some engraved pieces listed alongside matching drinking glasses, were these originally sold as complete sets or just put together later on?

Makers frequently sold them as night service sets. These included the carafe, a matching tumbler, and sometimes a small tray for the bedroom. Water sets for the dining table also came in matching suites. You'll often see subtle differences in the engraving of a set, as each piece was decorated by hand.