runtimeDesc

A NAMED method descriptor with its class references rewritten into the runtime namespace, so it can be compared against one read off live reflection. Unmapped names — JDK, library, mod types — pass through, which is correct: they are spelled the same in both namespaces.

Needed because the two namespaces disagree about CLASS names on every runtime that renames them (spigot's BlockPos is BlockPosition, fabric's is class_2338). Forge is the one where this is the identity.