feat: add advanced example of contract state migration

[denbite]

This example was built inspired by DevHub Contract
I believe this elegant and scalable approach is the way to go for contracts that often roll out breaking changes to their contract's code on mainnet

[frol]

@denbite I love it! Thank you for extracting the best practice and documenting it clearly

@race-of-sloths score 13

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Current status: executed

Reviewer	Score
@akorchyn	13

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❌ PR inactive

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[denbite]

@race-of-sloths include

[akorchyn]

@race-of-sloths score 13