Add OpenZeppelin remappings for improved developer experience

[xana-rahmani]

Description

This pull request introduces import remappings for OpenZeppelin contracts to the remappings.txt file.

[galekseev]

Remappings are temporary solutions. We're removing them in the future.
There is no need in open zeppelin libraries mapping.

[xana-rahmani]

Hi @galekseev
Thanks for reopening this PR. I understand that the team is planning to move away from remappings in the future. However, I believe merging this change in the meantime would be beneficial for anyone reading the code, as it resolves errors in IDEs and improves overall readability.
This is a straightforward change that can be easily removed when the planned future refactoring takes place.

Thank you for your consideration.

[galekseev]

After internal discussion we decided to close PR without merging.
The issue with openzepplin libraries mapping is solved with forge install command without adding additional remappings.
In PR #141 the command is implemented through postinstall task in package.json which also is called with yarn.
So it is enough to call yarn after downloading the clean repo.