Did the Fishguard expedition bring siege artillery?

Did the French bring siege artillery for the invasion?

No. They planned to have some cannon, but the force did not carry siege artillery.

The expedition did not bring siege artillery, though it planned to have some cannon. A landing boat later foundered with much of that artillery and its ammunition. Fishguard Fort's narrow approach remained defensible with a small garrison, especially against troops lacking guns. The presence of some planned cannon therefore did not amount to a force equipped to reduce fortified positions.