The stats for the ship give a defense of "1 - - 0" (Fore, Port, Starboard, Aft). Does that mean it has forward shields that wrap around to cover the forward half of the sides? Or are the arcs the usual 90 degrees and only that front arc is covered (if so, then why the '-' stats for the sides)?

I'm probably making this more complicated then it needs to be.

Ships under a certain size (I think Silhouette <4) only have front and aft arcs.

Exactly as Kshatriya said. Anything Sil 5 and above has all 4 zones for shields, whilst the Sil 4 and below is only fore and aft. The "-" is just a "not applicable" in this case. I believe the sheets for it often just show a fore/aft and no locations for the port and starboard.

Yeah, anything Sil 4 or less doesn't have side defensive arcs, just forward and aft. Check all the fighters you'll see the same.

Also remember how shields work in this system, so when you look at the numbers it's actually better that fighters have only two arcs and big ships have four.