One per-process rlimit as configured on a `Command`: the resource, and the soft and hard values to apply to it — the pair `setrlimit(2)` itself takes. Read back from `Command.Rlimits`; built by `Command.Rlimit`, which validates the pair at the builder boundary. The **soft** value is the limit actually in force (exceeding it raises this resource's signal or fails the operation); the **hard** value is the ceiling the child may raise its own soft value back up to. Both are in the resource's native unit (see `RlimitResource`), and `Soft` never exceeds `Hard`.