Add Levit Review Document

[atoumbre]

Added REVIEW.md containing a comprehensive assessment of Levit packages, covering Developer Experience, Performance, Adoption, and Contribution potential, adopting the persona of a seasoned Flutter GetX developer.

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PR created automatically by Jules for task 12767073255206738062 started by @atoumbre

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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