calculateBundlePricing returns incorrect (negative gas for EIP-1559 tx)

gasPricePaidBySearcher here is the priority fee -- it's already 'above' the base fee so subtracting base gas makes it go negative...

```
private calculateBundlePricing(
bundleTransactions: Array,
baseFee: BigNumber
) {
console.log('DBG__ bundle Transactions = ', bundleTransactions);
const bundleGasPricing = bundleTransactions.reduce(
(acc, transactionDetail) => {
const gasUsed = 'gas_used' in transactionDetail ? transactionDetail.gas_used : transactionDetail.gasUsed
const gasPricePaidBySearcher = BigNumber.from(
'gas_price' in transactionDetail ? transactionDetail.gas_price : transactionDetail.gasPrice
)
const priorityFeeReceivedByMiner = gasPricePaidBySearcher.sub(baseFee) <<<<<<------------------- THIS is incorrect
```

Locate calculateBundlePricing in the TypeScript source and trace how gas_price or gasPrice is interpreted for EIP-1559 transactions. Check the bundle pricing behavior around the priority-fee calculation, then verify that EIP-1559 bundle pricing no longer produces a negative gas value.

Written by the indexing model from the issue text.