Feature request: allow bundles to contain already included txs

[pyggie]

Similar to the revertingTxHashes array in a bundle, add another element like alreadyIncludedTxHashes specifying transactions that may have already been included earlier in the block or confirmed in a previous block. Such transactions would simply be skipped and dropped from the bundle.

Motivation example: multiple opportunities after an oracle update confirms or after a big multi-DEX trade.

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A more advanced version would allow specifying one or more sets of "at least one of these txs must have already been included, else include the first one". For example, the list of bundle transactions could be enriched to something like

bundle: [
  { type: 'raw-tx', rawtx: txA },
  { type 'at-least-one-prerequisite', rawtxs: [ txB, txC, txD ] },
  { type: 'raw-tx', rawtx: txE }
]

would mean to the miner building the block:

• First include transaction txA.
• If any of txB or txC or txD has already been included earlier in this block or confirmed in a previous block, then include nothing. Otherwise, include txB.
• Then include transaction txE.

So this bundle on chain would have 2 or 3 transactions, either [txA, txE] or [txA, txB, txE], depending on what came earlier.

Motivation example: ability to handle prerequisite transactions with multiple pending variants at the same {from,nonce}.

[yzhou61]

A simple implementation would be to simply allow dropping of failed transactions. When the transaction is applied twice, the second one will fail, which today leads to the bundle not being included. With an option to drop failed ones, the rest of the bundle can still turn out to be profitable and pay the miner as intended.

[thegostep]

One of my worries is introducing unnecessary complexity to order types. There is a challenge of balancing simplicity with expressibility. Are there more generic ways of expressing dependence on the behavior of other transactions?