CTL2 v0.3.0

What changed

• Upgraded the public runtime schema dependency to Zod 4.
• Preserved the CTL2 task contract, CTL2 wire format, and CTL1 decoding compatibility.
• Upgraded Vitest and its coverage provider together to 5.0.4.
• Added Dependabot grouping and supported-major policies for the development toolchain.

Verification

• 64 unit tests pass with 99.21% statement, 80.64% branch, and 100% function/line coverage.
• Documentation, TypeScript, ESM, CommonJS, consumer types, package contents, packed tarball, and Publint checks pass.
• Runtime verification passes on Node.js 18, 20, 22, and 24.
• Dependency review, audit, and CodeQL pass with no reported vulnerabilities.