Subsystem: Verification & Nyquist Completion Gate

Enforces Law 6: Completion requires deterministic evidence (src/verification/).

The 7-Tier Verification Hierarchy

Tier 1: Deterministic Check (file presence, syntax, hash consistency)
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Tier 2: Compiler Check (cargo check, type verification)
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Tier 3: Test Runner (cargo test, pytest, npm test)
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Tier 4: Static Analysis (clippy, formatting, linter)
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Tier 5: Diff & Invariants (workspace baseline snapshot matching)
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Tier 6: Automated Reviewer (independent review role audit)
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Tier 7: Failure Diagnosis (diagnostician analysis on failure)

Fail-fast gating halts downstream checks immediately if an earlier tier fails.