fix(rule): catch unsafe boolean guards

[GSTJ]

Summary

The rule now catches JSX guards that rely on a redeclared variable, the wrong initializer scope, or a replaced Boolean.

Details

• Resolves each initializer from the lexical scope where the declaration appears.
• Rejects ambiguous var redeclarations and every write after the trusted initializer.
• Treats a shadowed or reassigned Boolean as unsafe, with !! as the autofix fallback.

Testing steps

1. From the repository root, run:

pnpm install --frozen-lockfile
pnpm run test --runInBand

2. Confirm the command reports that all tests passed.

[github-actions]

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[GSTJ]

Proof from 3e86d35: published 1.3.8 returns zero diagnostics for all three cases. The packed branch fixes them on ESLint 3 with Node 14 and ESLint 10 with Node 24.

The frozen install, audit, lint, format, typecheck, tests, build, changelog checks, release controls, and tarball pack all pass.