Go 1.26.5 maps each test binary's stdout and stderr to the same product writer. Teach the captured executor to share one open file description for byte-equal output paths, then make directory test products emit that one ordered capture on coordinator stdout. Build captures and inherited-stdio routes remain unchanged.\n\nKeep the executor mechanism, package policy, native Cstage/WWstage proof, and normative contract together so every commit preserves the observable test-output behavior.
Separate import lookup from raw CLI target compatibility in both production drivers. Package scans and test-support edges now create directory nodes only, while unit composition emits only the owning package's sorted sources after direct export data. Document the Go 1.26.5 ownership evidence and retained single-file root boundary.
Make the schema-1 transcription mechanically consistent before the protocol freeze: restore compiler-protocol identity, use the typed native-contract record identity, distinguish encoding and path classes, and close the package artifact kinds. These corrections must land together because one exhaustive IDL cannot encode the prior conflicting rules.