Add Account framework

[ernestognw]

Moves the community contracts account abstraction framework to this repository.
Check #5664 before

It just moves files from community contracts. To review, it's enough if you go over files and check whether there are differences from the community repository

PR Checklist

• Tests
• Documentation
• Changeset entry (run npx changeset add)

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🦋 Changeset detected

Latest commit: 9542779

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
openzeppelin-solidity	Minor

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[ernestognw]

As part of the upgradeable transpilation pipeline, we generate the upgradeable versions and the run tests against them. However, ERC-7702 accounts will delegate to an EIP-712 (through ERC7739) contract, so the domain separator will be rebuilt each time without the name or version set in the EOA's storage.

In practice, if users are delegating to an upgradeable contract, it should be a proxy pointing to an implementation that uses the EIP712Upgradeable version so that the domain can be initialized (and reinitialized) properly.