✨ Quality: test coverage - Dialog component branch logic

[galiprandi]

I have improved the test coverage for the Dialog component.

💡 What

Added new unit tests to lib/components/Dialog/index.test.tsx that exercise previously uncovered branch logic in the handleClick method and verify that optional callbacks (onOpen, onClose) are handled safely when omitted.

🎯 Why

The branch coverage for the Dialog component was at 92%, leaving some edge cases in the event handling logic untested. Specifically, the "falsy" branches for closeOnBackdropClick and behavior !== 'modal' were not covered.

📊 Impact

• Increased branch coverage for lib/components/Dialog/index.tsx from 92% to 96%.
• Improved robustness of the Dialog component by ensuring it behaves correctly when optional props are missing.
• Aligned the test suite with the project's quality goal of achieving 100% branch coverage for optional callbacks and defensive logic.

✅ Verification

• Ran pnpm test lib/components/Dialog/index.test.tsx (all tests passed).
• Ran pnpm test:coverage and confirmed the coverage increase for the Dialog component.
• Ran pnpm eslint and npx prettier on the modified file.

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PR created automatically by Jules for task 8957963541406261672 started by @galiprandi

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