Brummel
a8bd52eaff
FieldSpec.name was &'static str, forcing derive_signature to Box::leak every re-exported composite OutField name. Because compile_with_params reruns derive_signature per sweep point, an N-point sweep over an M-output-field composite leaked N×M boundary names unbounded — a scaling wall the moment the World/sweep layer compiles families per point. Pull FieldSpec.name to String, mirroring the already-owned PortSpec.name and ParamSpec.name: a composite re-exports interior fields under runtime boundary names, so ownership is the correct model, not a workaround. FieldSpec loses Copy; the only fallout is one borrow at the render site. leak_name/Box::leak deleted. Behaviour-preserving: signature contents unchanged, all 231 tests green.