Retune precision for monorepo false positives

[alxxjohn]

Summary

• harden precision rules for false positives across UI helpers, integration adapters, scripts, routing/orchestration, duplicated enum literals, and central data-client fan-in
• keep real hidden-mutation and collaborator side-effect coverage with focused tests
• remove the need for downstream waivers while preserving zero findings with the retuned scanner

Verification

• env -u GOROOT GOCACHE=/private/tmp/codeguard-go-cache go test ./tests/checks -run 'Test(FunctionHiddenMutation|FunctionCommandQueryMix|QualityNaming|QualityDuplicatedKnowledge|Defensive|Design|Environment|Switch|QualityAI|LocalDesign)'
• downstream no-waiver scan with rebuilt branch binary: total findings 0

[alxxjohn]

Superseded by sanitized replacement PR #90.