fix(knowledge): bind promotions to verified source snapshots

[drewstone]

Concurrent run-local edits could make promotion copy content that its citation check never inspected, then record the digest of an older page.
Promotion now captures each selected page and its cited support, verifies their canonical page identities against the inspected snapshot, and transfers those captured strings.
A changed identity raises path-conflict before shared pages are written.
Edits after capture cannot replace the promoted version.

The package advances to 16.0.1 without changing public contracts.

Validation:

• The new claim/support race regressions failed before the fix and pass afterward.
• All 7 promotion tests pass, including a source edit after capture, matching receipt digests, and an untouched unselected page.
• Ubuntu CI passed 876 tests with 7 skips, lint, typecheck, build, package lifecycle/API verification, and compatibility with Eval 0.174.
• The official optimizer job passed its GEPA and SkillOpt integration tests.
• The version gate and diff checks pass locally.
• A Linux Node 22 recheck passed all 151 tests across the affected local failure suites and promotion.
  It used an init process, temporary in-memory test storage, and one worker without changing test timeouts.

The Darwin full suite encountered the existing Linux-only exact-candidate boundary.
The initial Docker run encountered one unreaped zombie and eight timeouts.
The corrected container recheck and ordinary Ubuntu CI passed without further source changes.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-12T23:07:22.267095Z	dd7266b	PR opened

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