Add decision-model tag (#1)

clef_mlx.py: add 'predict' CLI and 'serve' (local POST /v1/systemone server); card: CLI and server docs

Card: zero-shot-classification tag, RAM guide for all variants, limitations, pinned mlx-vlm; clef_mlx: warn on untested mlx-vlm/mlx-lm versions

Add Decision Index quality check; clef_mlx: strict no-truncation mode (truncate=False)

Add MLX 4-bit conversion of Cloudflare/clef with joint schema head and clef_mlx.py loader