fix(l2geth): misc timestamp fixes

Monotonicity violations were being reported in two locations, once in
the sync service and then later in the worker. Because of recent updates
in the sync service, there's never a case where monotonicity violations
would not be caught first within the sync service. This code path only
triggered within L1 syncing verifiers and caused issues with unintended
timestamp manipulation.

.changeset/green-donuts-bathe.md

+---
+'@eth-optimism/l2geth': patch
+---
+
+Fixes incorrect timestamp handling for L1 syncing verifiers

l2geth/miner/worker.go

@@ -931,18 +931,7 @@ func (w *worker) commitNewTx(tx *types.Transaction) error {
 	// Preserve liveliness as best as possible. Must panic on L1 to L2
 	// transactions as the timestamp cannot be malleated
 	if parent.Time() > tx.L1Timestamp() {
-		log.Error("Monotonicity violation", "index", num)
-		if tx.QueueOrigin() == types.QueueOriginSequencer {
-			tx.SetL1Timestamp(parent.Time())
-			prev := parent.Transactions()
-			if len(prev) == 1 {
-				tx.SetL1BlockNumber(prev[0].L1BlockNumber().Uint64())
-			} else {
-				log.Error("Cannot recover L1 Blocknumber")
-			}
-		} else {
-			log.Error("Cannot recover from monotonicity violation")
-		}
+		log.Error("Monotonicity violation", "index", num, "parent", parent.Time(), "tx", tx.L1Timestamp())
 	}
 
 	// Fill in the index field in the tx meta if it is `nil`.

l2geth/rollup/sync_service.go

@@ -825,13 +825,14 @@ func (s *SyncService) applyTransactionToTip(tx *types.Transaction) error {
 		if now.Sub(current) > s.timestampRefreshThreshold {
 			current = now
 		}
+		log.Info("Updating latest timestamp", "timestamp", current, "unix", current.Unix())
 		tx.SetL1Timestamp(uint64(current.Unix()))
 	} else if tx.L1Timestamp() == 0 && s.verifier {
 		// This should never happen
 		log.Error("No tx timestamp found when running as verifier", "hash", tx.Hash().Hex())
-	} else if tx.L1Timestamp() < s.GetLatestL1Timestamp() {
+	} else if tx.L1Timestamp() < ts {
 		// This should never happen, but sometimes does
-		log.Error("Timestamp monotonicity violation", "hash", tx.Hash().Hex())
+		log.Error("Timestamp monotonicity violation", "hash", tx.Hash().Hex(), "latest", ts, "tx", tx.L1Timestamp())
 	}
 
 	l1BlockNumber := tx.L1BlockNumber()