Add Batch messages from processor, verify Batchs published on-chain

Renames Update to SignedBatch.

Checks Batch equality via a hash of the InInstructions. That prevents needing
to keep the Batch in node state or TX introspect.

processor/src/main.rs

@@ -530,6 +530,12 @@ async fn run<N: Network, D: Db, Co: Coordinator>(mut raw_db: D, network: N, mut
             for batch in batches {
               info!("created batch {} ({} instructions)", batch.id, batch.instructions.len());
 
+              coordinator.send(
+                messages::ProcessorMessage::Substrate(
+                  messages::substrate::ProcessorMessage::Batch { batch: batch.clone() }
+                )
+              ).await;
+
               if let Some(substrate_signer) = tributary_mutable.substrate_signer.as_mut() {
                 substrate_signer.sign(txn, batch).await;
               }
@@ -588,9 +594,9 @@ async fn run<N: Network, D: Db, Co: Coordinator>(mut raw_db: D, network: N, mut
           }
           SubstrateSignerEvent::SignedBatch(batch) => {
             coordinator
-              .send(ProcessorMessage::Substrate(messages::substrate::ProcessorMessage::Update {
-                batch,
-              }))
+              .send(ProcessorMessage::Substrate(
+                messages::substrate::ProcessorMessage::SignedBatch { batch },
+              ))
               .await;
           }
         }

processor/src/multisigs/scanner.rs

@@ -694,6 +694,7 @@ impl<N: Network, D: Db> Scanner<N, D> {
             return;
           }
 
+          // Since we're creating a Batch, mark it as needing ack
           scanner.need_ack.push_back(block_being_scanned);
           true
         } else {
@@ -706,7 +707,7 @@ impl<N: Network, D: Db> Scanner<N, D> {
           scanner.eventualities.remove(retired.to_bytes().as_ref());
         }
 
-        // Update ram_scanned/need_ack
+        // Update ram_scanned
         scanner.ram_scanned = Some(block_being_scanned);
 
         drop(scanner_lock);