Refactor: Introduce get_peers_for_blinded_path utility

Added a new helper function to encapsulate the logic for
fetching peers used in blinded path creation.

This keeps the code DRY by reducing duplication and makes
the logic easier to reuse across different message routers.

Author: shaavan

lightning/src/ln/channelmanager.rs

@@ -10870,6 +10870,23 @@ where
 		now
 	}
 
+	fn get_peers_for_blinded_path(&self) -> Vec<MessageForwardNode> {
+		self.per_peer_state.read().unwrap()
+			.iter()
+			.map(|(node_id, peer_state)| (node_id, peer_state.lock().unwrap()))
+			.filter(|(_, peer)| peer.is_connected)
+			.filter(|(_, peer)| peer.latest_features.supports_onion_messages())
+			.map(|(node_id, peer)| MessageForwardNode {
+				node_id: *node_id,
+				short_channel_id: peer.channel_by_id
+					.iter()
+					.filter(|(_, channel)| channel.context().is_usable())
+					.min_by_key(|(_, channel)| channel.context().channel_creation_height)
+					.and_then(|(_, channel)| channel.context().get_short_channel_id()),
+			})
+			.collect::<Vec<_>>()
+	}
+
 	/// Creates a collection of blinded paths by delegating to
 	/// [`MessageRouter::create_blinded_paths`].
 	///
@@ -10878,16 +10895,7 @@ where
 		let recipient = self.get_our_node_id();
 		let secp_ctx = &self.secp_ctx;
 
-		let peers = self.per_peer_state.read().unwrap()
-			.iter()
-			.map(|(node_id, peer_state)| (node_id, peer_state.lock().unwrap()))
-			.filter(|(_, peer)| peer.is_connected)
-			.filter(|(_, peer)| peer.latest_features.supports_onion_messages())
-			.map(|(node_id, _)| MessageForwardNode {
-				node_id: *node_id,
-				short_channel_id: None
-			})
-			.collect::<Vec<_>>();
+		let peers = self.get_peers_for_blinded_path();
 
 		self.message_router
 			.create_blinded_paths(recipient, context, peers, secp_ctx)
@@ -10902,20 +10910,7 @@ where
 		let recipient = self.get_our_node_id();
 		let secp_ctx = &self.secp_ctx;
 
-		let peers = self.per_peer_state.read().unwrap()
-			.iter()
-			.map(|(node_id, peer_state)| (node_id, peer_state.lock().unwrap()))
-			.filter(|(_, peer)| peer.is_connected)
-			.filter(|(_, peer)| peer.latest_features.supports_onion_messages())
-			.map(|(node_id, peer)| MessageForwardNode {
-				node_id: *node_id,
-				short_channel_id: peer.channel_by_id
-					.iter()
-					.filter(|(_, channel)| channel.context().is_usable())
-					.min_by_key(|(_, channel)| channel.context().channel_creation_height)
-					.and_then(|(_, channel)| channel.context().get_short_channel_id()),
-			})
-			.collect::<Vec<_>>();
+		let peers = self.get_peers_for_blinded_path();
 
 		self.message_router
 			.create_compact_blinded_paths(recipient, MessageContext::Offers(context), peers, secp_ctx)