fix(mlx-vlm): pin upstream to v0.4.4 to unblock CUDA builds (#9568)

Blaizzy/mlx-vlm git HEAD bumped its constraint to mlx>=0.31.2, but
mlx-cuda-12 and mlx-cuda-13 are only published up to 0.31.1 on PyPI.
Since mlx[cudaXX]==0.31.2 forces a sibling wheel that doesn't exist,
pip backtracks through every older mlx[cudaXX], none of which satisfy
mlx>=0.31.2, producing ResolutionImpossible.

Pin all variants to the v0.4.4 tag (mlx>=0.30.0), which resolves
cleanly against mlx[cuda13]==0.31.1. cpu/mps weren't broken yet but
are pinned for consistency.

Assisted-by: Claude:claude-opus-4-7

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>