eth: manually unsubscribe if we break remote_subscription due to error

kinode/src/eth/subscription.rs

@@ -470,7 +470,7 @@ async fn maintain_remote_subscription(
                     true,
                     Some(30),
                     IncomingReq::SubKeepalive(remote_sub_id),
-                    &send_to_loop,
+                    send_to_loop,
                 ).await;
             }
             _incoming = net_error_rx.recv() => {
@@ -487,6 +487,23 @@ async fn maintain_remote_subscription(
             }
         }
     };
+    // tell provider node we don't need their services anymore
+    // (in case they did not close the subscription on their side,
+    // such as in the 2-hour timeout case)
+    kernel_message(
+        our,
+        rand::random(),
+        Address {
+            node: provider_node.to_string(),
+            process: ETH_PROCESS_ID.clone(),
+        },
+        None,
+        true,
+        None,
+        EthAction::UnsubscribeLogs(sub_id),
+        send_to_loop,
+    )
+    .await;
     active_subscriptions
         .entry(target.clone())
         .and_modify(|sub_map| {