feat: add additional payloadbody conversion fn (#1989)

* feat: add additional payloadbody conversion fn

* make non breaking

crates/rpc-types-engine/src/payload.rs

@@ -1088,13 +1088,24 @@ pub struct ExecutionPayloadBodyV1 {
 }
 
 impl ExecutionPayloadBodyV1 {
-    /// Converts a [`alloy_consensus::Block`] into an execution payload body.
-    pub fn from_block<T: Encodable2718, H>(block: Block<T, H>) -> Self {
+    /// Creates an [`ExecutionPayloadBodyV1`] from the given withdrawals and transactions
+    pub fn new<'a, T>(
+        withdrawals: Option<Withdrawals>,
+        transactions: impl IntoIterator<Item = &'a T>,
+    ) -> Self
+    where
+        T: Encodable2718 + 'a,
+    {
         Self {
-            transactions: block.body.transactions().map(|tx| tx.encoded_2718().into()).collect(),
-            withdrawals: block.body.withdrawals.map(Withdrawals::into_inner),
+            transactions: transactions.into_iter().map(|tx| tx.encoded_2718().into()).collect(),
+            withdrawals: withdrawals.map(Withdrawals::into_inner),
         }
     }
+
+    /// Converts a [`alloy_consensus::Block`] into an execution payload body.
+    pub fn from_block<T: Encodable2718, H>(block: Block<T, H>) -> Self {
+        Self::new(block.body.withdrawals.clone(), block.body.transactions())
+    }
 }
 
 impl<T: Encodable2718, H> From<Block<T, H>> for ExecutionPayloadBodyV1 {