[ITSGJY]

Summary

Complete the model-facing project validation contract and harden native Node TAP evidence within the existing project_validate lifecycle (refs yyjeqhc#962).

• C0 — contract accuracy: Document bounded Node script checks and exact-opt-in native TAP tests; distinguish Python pytest and Ruff capabilities; disclose that project tests/scripts may have filesystem and network effects. Keep public ToolCall/ToolSpec schema shapes and Runner admission unchanged.
• C1 — TAP evidence: Require one unindented root 1..N plan adjacent to the canonical eight-line terminal footer, with matching contiguous root ok/not ok ordinals. Preserve nested-suite indentation, reject repeated numeric accounting, and accept ordinary Node t.diagnostic comments. Use the existing evidence parser and Job projection: malformed or truncated output cannot prove tests, even with require_tests=false.
• Add source-grounded red/green regressions for nested-only or duplicated plans, root ordinal mismatch, duplicate accounting entries, legitimate diagnostics, suites, pass/fail, skip/TODO and zero tests. Preserve the Node test node --test --test-reporter=tap Runner-owned fixed-argv contract.

Local validation and review

• cargo test --locked -p webcodex-core --lib: 334 passed.
• cargo test --locked -p webcodex-tool-contracts --lib: 297 passed.
• cargo fmt --all -- --check and git diff --check: passed.
• Real Node v26.10.0 native TAP pass/fail/nesting/skip/TODO and diagnostic output collected in isolated, automatically cleaned fixtures.
• Independent Codex and AGY reviews: PASS with no actionable P0/P1/P2 blockers. A Codex P2 false-rejection finding was independently reproduced via Node t.diagnostic, fixed and covered by regression tests.
• Clean rebase onto 6f8ed6d8c3ba5ffa163a4e717f6039ca1d85952e; both stable patch-ids unchanged across the rebase.

Exact candidate: 7d4354fe37a140ab78c90e70d5f9184a95cdeb29.

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