Wire sigrok and tshark finalization to the effective signal. Services and file-failure adapters retain exact opaque reasons and completed Evidence instead of guessing from error names. Preserve typed primary outcomes through failed cleanup and recovery.
Validation: latest per-file coverage is 114 passing tests across nine selected files with 14 explicit Linux-only skips; core foundation passes independently. check:fast, docs and discovery pass. Four finalization controls failed before the signal ownership fix. Bounded completed authored-producer service workflows have identical Evidence with no performance improvement claim. Real sigrok/tshark and native Linux/Windows were not verified.
Closes#4858