EIP-4844 proposed the new (type-3) Blob Transactions which are expensive
(because blobs are big etc.). The tx-pool should be tightened to
alleviate spam and dos attacks by way of these new transactions.
### Changes
**Keep blob txs cached**
During new block, don't delete mined blobTxs, instead cache it till they
are finalized. This is to avoid fetching them again for unwind. During
unwind, if it's a previously seen blobTxn, try to fetch it from memory.
**Pool config**
BlobSlots: Similar to AccountSlots - limits how many blobs a single
account is allowed to have until it's marked as spamming.
Blob txn priceBump: It's an added field in pool config (with a flag).
Defaults to 100%, since blob txs of equal fee are costlier to
process/execute
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Co-authored-by: alex.sharov <AskAlexSharov@gmail.com>
The default 2 min SyncToNewPeersEvery seems like too big a value for txn
propagation. So, changing the default to something like 5 sec w/o
introducing a flag.
