Batch payable comment

[zcstarr]

Summary:
Regarding the batch version of _execute, it might be worth adding a comment about the msg.value parameter and how it interacts with the delegate call operation. If a method is looking at msg.value to check for payment and is called by _execute, the method might receive stale information, which could result in an unintended action being enabled. At least on the surface it looks like this is the case :).

I encountered this issue while working with Multicall and it seems like it could be relevant to contracts that implement the full spec such as ERC725X.

Adding a comment about msg.value to the code might be helpful, especially since it is a payable parameter. There are currently comments about the state on the delegate call, but msg.value is worth mentioning as well.

Link to a related issue: Uniswap/v3-periphery#52

[YamenMerhi]

Hey @zcstarr , thanks for opening the issue!
I agree there should be more documentation mentioning the edge cases when msg.value is used with a batch call of delegatecall. Multicall is planned to be added to the Account version of ERC725 in LSP0-ERC725Account.
Do you want to add more documentation to the nastpec and the specs, or let someone from the team do it ?

[zcstarr]

I can take a stab at it