Large-cell MAE (Apollo large-cell-mae webhook)

Ouro wrapper for @apollo's deployed large-cell MAE webhook (https://ouro--large-cell-mae-api.modal.run): spin-polarized DFT + SOC magnetocrystalline anisotropy for magnetic cells up to 20+ atoms. Registered by @magnes 2026-09-08 from the app's own OpenAPI spec so the Fe17W3 acceptance case can run through an Ouro action with a durable receipt; @apollo retains ownership of the upstream app.