Another attempt at #25380 with an alternate approach
This PR updates CBlockPolicyEstimator
to ignore all transactions that are CPFP’d by some child when a new block is received.
This fixes the assumption that all transactions are confirmed solely because of their fee rate.
As some transactions are confirmed due to a CPFP by some child.
This approach linearize all transactions removed from the mempool because of the new block, and only ignore transactions whose mining score is not the same with their the fee rate.
All transaction with in-mempool parent are already not tracked for fee estimation, so the child that CPFP’d the parent is also ignored.
Upon implementing the cluster mempool, we will just track chunks and make the fee estimator package aware.