fix(pre1): retain required build-stage and command evidence

[RobLe3]

Scope

• Emit content-free command lifecycle events without logging argv or environment values.
• Declare required build stages and persist bounded PASS/FAIL/NOT_RUN/INCOMPLETE evidence before disposable build cleanup.
• Preserve native failures when diagnostic persistence also fails; required evidence failure cannot become a successful stage.
• Keep ordinary runtime APIs, package versions and release authority unchanged.

Validation

• Component artifact-builder and command-observation regression suites pass locally.
• Cross-component seven-case required-stage rehearsal passes, including a real dependency-free Cargo failure after disposable cleanup.
• Portable local CI preflight passes on the committed source; platform-only exclusions remain explicit.
• This does not supply clean Windows artifact, integration, performance or qualification credit. Full per-test inventories remain a final qualification gate.

Review boundary

This follow-up is separate from the already merged Windows runtime fixes. Review this commit independently before advancing any candidate source pin. No package publication, AWS allocation or deployment is included.

[RobLe3]

Bounded instrumentation review at 079f6c1: required-stage declaration and ordered execution retain PASS/FAIL/NOT_RUN/INCOMPLETE separately from optional command events; native failure is preserved when required terminal evidence cannot persist. Public runtime and authority surfaces are unchanged. Reviewed helper/caller changes and regression evidence; component tests, cross-component ledger/Cargo rehearsal and exact-head portable CI passed. Required hosted checks are now SUCCESS. No merge-blocking finding in this scope. Actual source-bound Windows artifact execution remains pending; no qualification or historical root-cause claim follows. Merge is separate from runtime-fix PRs and source-pin promotion.