An update to this post
So on a whim I googled for “lady of the forge”, and got a wealth of results. They all pointed to Brigid, goddess of the hearth, forge, and fire, patron of smiths and poets, among others.
I’d heard of Brigid before, and I’ve always enjoyed watching blacksmiths at work, but I knew nothing of a Lady of the Forge until now. As far as I can tell she emerged spontaneously from my unconscious.