pub fn parse_decode_ring_slots(s: &str) -> Result<Option<usize>, String>Expand description
2026-09-25: Parses --ssm-decode-ring-slots: auto gives None (fit at
preflight), a number up to DECODE_ROLLBACK_RING_SLOTS gives Some, and
anything else an error. validate_serve_args and publish_kernel_flags
both parse through this.