ethereum, ethclient: add FeeHistory support (#25403)

Co-authored-by: Felix Lange <fjl@twurst.com>

interfaces.go

@@ -201,6 +201,15 @@ type GasPricer interface {
 	SuggestGasPrice(ctx context.Context) (*big.Int, error)
 }
 
+// FeeHistory provides recent fee market data that consumers can use to determine
+// a reasonable maxPriorityFeePerGas value.
+type FeeHistory struct {
+	OldestBlock  *big.Int     // block coresponding to first response value
+	Reward       [][]*big.Int // list every txs priority fee per block
+	BaseFee      []*big.Int   // list of each block's base fee
+	GasUsedRatio []float64    // ratio of gas used out of the total available limit
+}
+
 // A PendingStateReader provides access to the pending state, which is the result of all
 // known executable transactions which have not yet been included in the blockchain. It is
 // commonly used to display the result of ’unconfirmed’ actions (e.g. wallet value