✨ Improve EIP7702Proxy and add LibEIP7702

[Vectorized]

Description

LibEIP7702 makes it neater to work with the proxy.

Principles:

• Try to preserve the upper 96 bits. Just in case some weird delegation saved some values in there.
• Use transient storage to pass the request. Technically, we can just use regular storage, without much overhead, cuz it's warm. But I am worried about the super edge case where someone actually use the upper 96 bits. Also it's cheaper for the case of direct delegation (no via EIP7702Proxy).

Checklist

Ensure you completed all of the steps below before submitting your pull request:

• Ran forge fmt?
• Ran forge test?

Pull requests with an incomplete checklist will be thrown out.

[github-actions]

Gas Snapshot Comparison Report

Generated at commit : 8aaf8aa, Compared to commit : 29b5dbe

Contract Name	Test Name	Main Gas	PR Gas	Diff
EIP7702ProxyTest	testEIP7702Proxy()	31850	-	-
	test__codesize()	6590	-	-

[Vectorized]

Should we add some kind of identifier to the proxy?

[Vectorized]

Marinating for the next 6 hours, then merging. @atarpara

[atarpara]

LGTM.

[atarpara]

Should we add some kind of identifier to the proxy?

We can use proxy codehash as a identifier.