Ensure tsconfig types and dev warning

[seveibar]

Summary

• add coverage to the init CLI test to assert the generated tsconfig includes the tscircuit type definition
• emit a yellow warning from tsci dev when the project's tsconfig is missing the tscircuit type so users can fix it proactively

Testing

• bun test tests/cli/init/init.test.ts
• bunx tsc --noEmit

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Codex Task

[tscircuitbot]

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PR Rating: ⭐
Impact: Tiny

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