watchlist add: event only if inserted; adr 0015 jetstream/relay accuracy; drop vacuous assert

crates/application/tests/diary/review_logger_test.rs

@@ -270,7 +270,6 @@ async fn a_refused_save_propagates_and_records_nothing() {
         .await;
 
     assert!(result.is_err());
-    assert_eq!(movies.review_count(), 0);
     assert!(movies.recorded_events().is_empty());
 }
 

crates/application/tests/watchlist/add_test.rs

@@ -54,6 +54,11 @@ async fn adding_a_movie_already_on_the_watchlist_is_idempotent() {
     add::execute(&deps, make_cmd()).await.unwrap();
     add::execute(&deps, make_cmd()).await.unwrap();
 
+    assert_eq!(
+        movies.recorded_events().len(),
+        1,
+        "the repeat inserted nothing, so it announces nothing"
+    );
     assert_eq!(
         watchlist.watchlist_count(),
         1,