feat: update sequencer L1 message index based on BlockImportOutcome

Author: greged93

crates/manager/src/manager/mod.rs

@@ -454,6 +454,9 @@ where
         match event {
             EngineDriverEvent::BlockImportOutcome(outcome) => {
                 if let Some(block) = outcome.block() {
+                    if let Some(sequencer) = self.sequencer.as_mut() {
+                        sequencer.handle_new_payload(&block);
+                    }
                     if let Some(event_sender) = self.event_sender.as_ref() {
                         event_sender.notify(RollupManagerEvent::BlockImported(block.clone()));
                     }

crates/sequencer/src/lib.rs

@@ -193,7 +193,11 @@ where
     pub fn handle_new_payload(&mut self, block: &ScrollBlock) {
         let queue_index = block.body.transactions.iter().filter_map(|tx| tx.queue_index()).max();
         if let Some(queue_index) = queue_index {
-            self.l1_messages_queue_index = queue_index + 1;
+            // only update the queue index if it has advanced
+            if queue_index + 1 > self.l1_messages_queue_index {
+                tracing::trace!(target: "rollup_node::sequencer", "Advancing L1 messages queue index from {} to {}", self.l1_messages_queue_index, queue_index + 1);
+                self.l1_messages_queue_index = queue_index + 1;
+            }
         }
     }
 }