baracuda-cuda-parse

CUDA -> IR frontend for the neutral `unpopped` kernel generator: the tree-sitter grammar binding (`parse_cuda`), the CUDA residue list, and the `CUDA` `Frontend` descriptor. Depends on the neutral generator `unpopped` (feature `convert`) and supplies the CUDA-specific parse-side surface from OUTSIDE the neutral core, mirroring `baracuda-cuda-emit`'s emit-side placement.