Slice #60: fail-closed finalize quality gate with structured errors

[AmirTlinov]

Closes #60

Summary

• enforce fail-closed finalize checklist: required scope, findings, and qa sections, with explicit qa.verdict
• keep draft workflow flexible: finalize checks are enforced only on Draft -> Finalized transition
• return structured actionable finalize validation errors (missing_sections, missing_fields, invalid_refs)
• validate ref integrity at finalize and block stale/broken anchors with section/ref/path/line details
• update README with finalize checklist and error details (EN/RU)

Tests

• domain finalize gate tests (positive + negative)
• integration tests for missing sections/fields, stale refs, and draft flexibility
• e2e test for structured finalize validation details + existing finalize success path updated

Required gates (local)

• cargo fmt --check
• cargo clippy --all-targets --all-features -- -D warnings
• cargo test --all-targets --all-features
• scripts/check_coverage_baseline.sh
• cargo audit

[AmirTlinov]

@review review

[AmirTlinov]

@review review\n\nSecond pass request after green required gates.

[AmirTlinov]

@review review\n\nThird/final request in this execution window. If no response, marking BLOCKED on review availability.

[AmirTlinov]

Review loop verdict: BLOCKED.

Reason: no response from @review review after 3 deterministic attempts in this execution window:

1. Slice #60: fail-closed finalize quality gate with structured errors #66 (comment)
2. Slice #60: fail-closed finalize quality gate with structured errors #66 (comment)
3. Slice #60: fail-closed finalize quality gate with structured errors #66 (comment)

No merge/close actions taken.

[AmirTlinov]

VERDICT: PASS

Scope checked: issue #60 only (README.md, src/adapters/mcp_stdio/error_contract.rs, src/app/input_usecases.rs, src/domain/errors.rs, src/domain/models.rs, tests/e2e.rs, tests/integration_test.rs).

Rationale (concise):

• Finalize is fail-closed for required baseline quality (scope, findings, qa.verdict).
• Finalize blocks stale/broken refs and returns structured, actionable details (missing_sections, missing_fields, invalid_refs).
• Draft flows remain unaffected until finalize transition.
• No scope creep into Slice: actionable expected_revision conflict diagnostics #62 semantics (revision_conflict contract unchanged).

Validation run:

• cargo fmt --check
• cargo test --all-targets --all-features
  Both passed on PR branch.