[MOON-863] add full proxy precompile (discussion)

[nbaztec]

What does it do?

adds proxy precompile

This PR is for discussion purposes on what to support in the proxy precompile after https://github.com/PureStake/moonbeam/pull/1705.

What important points reviewers should know?

Is there something left for follow-up PRs?

What alternative implementations were considered?

Are there relevant PRs or issues in other repositories (Substrate, Polkadot, Frontier, Cumulus)?

What value does it bring to the blockchain users?

[librelois]

All proxy precompile functions that take an encoded call as parameter should take bounded inputs, like this PR: https://github.com/PureStake/moonbeam/pull/1656

[nbaztec]

I'll wait for https://github.com/PureStake/moonbeam/pull/1656 to get merged, since it contains the necessary BoundedVec Read implementations.

[nanocryk]

@nbaztec Can now be updated to BoundedVec and precompile macro :)

[nbaztec]

Closing in favor of https://github.com/PureStake/moonbeam/pull/2022