Drop the NCII guard: it scores edit prompts and there is no image input

Run the NCII prompt guard on every request

Base schedule only, and length and slice move to Advanced options

Fix two API-only failures: None steps and a session-narrowed latent_index maximum

Reference decode recipe verbatim; length + latent_index controls; vendored strict loader

MiniMax-H3 as an image model: 5-frame floor, single-slice decode