[Feature]: Improvements for koba

[qalisander]

What is the feature you would like to see?

I think we shouldn't leave koba as it is and explore area of improvements:

• think how to store constructor logic next to contract logic and field declarations, e.g inside sol_storage! macro
• think how to spread constructor logic among inherited contracts and implementation, e.g. user of pausable shouldn't know how to instantiate it

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[alexfertel]

This one as well https://github.com/OpenZeppelin/rust-contracts-stylus/issues/145

[alexfertel]

This one too https://github.com/OpenZeppelin/rust-contracts-stylus/issues/128