Add ERC721 transfer CDE

[SebastienGllmt]

Right now we have an ERC721 CDE, but it only keeps track of new NFT mints

For transfers, we're instead relying on the generic CDE using something like this

abiPath: "./abis/ERC721.json"
eventSignature: "Transfer(address,address,uint256)"
scheduledPrefix: tradeTransfer

A good example of wanting to use this is the card game template we wanted to update the state machine when an NFT got burned (transferred to the 0 address). You can see documentation for that here

But it seems reasonable to want to have built-in CDE option for this (and maybe for other stds like ERC20, or even maybe a CDE for just regular ETH send instead of having to use a generic CDE over the GenericPayment contract)

I am a little concerned that we might might end up creating too many CDEs that are just shims over a Ethereum log event though.

Additionally, it's kind of strange that the erc721 CDE does keep track of transfers (and not just mints) internally to power utility functions like getNftOwner. I feels like the separation of concerns is not super clear (and this applies to a lesser extent with the ERC20 CDEs)

[SebastienGllmt]

To add to this, it would make sense to rename scheduledPrefix here to something like mintPrefix and then make it optional, just like we have burnScheduledPrefix optional