fix: use UnmarshalBinary for typed transaction decoding in proxy

The proxy server used rlp.DecodeBytes to decode captured transactions,
which only handles legacy transactions. Typed transactions (EIP-2718,
e.g. EIP-1559 type 2) have a type prefix byte before the RLP payload
that causes rlp.DecodeBytes to fail with 'typed transaction too short'.

Switch to Transaction.UnmarshalBinary() which handles both legacy and
typed transaction formats.

Also fix load-test worker config to include required fields for
calldata (max_size) and precompile (target) transaction types.

Author: meyer9

runner/clients/common/proxy/proxy.go

@@ -22,7 +22,6 @@ import (
 	"github.com/ethereum/go-ethereum/common"
 	ethTypes "github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/log"
-	"github.com/ethereum/go-ethereum/rlp"
 )
 
 type ProxyServer struct {
@@ -196,11 +195,13 @@ func (p *ProxyServer) OverrideRequest(method string, rawParams json.RawMessage)
 			return false, nil, fmt.Errorf("failed to decode hex: %w", err)
 		}
 
-		err = rlp.DecodeBytes(rawTxBytes, &tx)
+		// Use UnmarshalBinary to support both legacy and typed (EIP-2718) transactions.
+		// The previous rlp.DecodeBytes only handled legacy transactions.
+		err = tx.UnmarshalBinary(rawTxBytes)
 
 		if err != nil {
-			p.log.Error("failed to decode RLP", "err", err)
-			return false, nil, fmt.Errorf("failed to decode RLP: %w", err)
+			p.log.Error("failed to decode transaction", "err", err)
+			return false, nil, fmt.Errorf("failed to decode transaction: %w", err)
 		}
 
 		p.pendingTxs = append(p.pendingTxs, &tx)

runner/payload/loadtest/load_test_worker.go

@@ -39,8 +39,10 @@ type loadTestConfig struct {
 }
 
 type loadTestTransactionDef struct {
-	Type   string `yaml:"type"`
-	Weight uint64 `yaml:"weight"`
+	Type    string `yaml:"type"`
+	Weight  uint64 `yaml:"weight"`
+	MaxSize uint64 `yaml:"max_size,omitempty"`
+	Target  string `yaml:"target,omitempty"`
 }
 
 type loadTestPayloadWorker struct {
@@ -159,8 +161,8 @@ func (w *loadTestPayloadWorker) writeConfig() (string, error) {
 		FundingAmount: "10000000000000000000",
 		Transactions: []loadTestTransactionDef{
 			{Type: "transfer", Weight: 70},
-			{Type: "calldata", Weight: 20},
-			{Type: "precompile", Weight: 10},
+			{Type: "calldata", Weight: 20, MaxSize: 256},
+			{Type: "precompile", Weight: 10, Target: "sha256"},
 		},
 	}