test(tracker-core): wait for downloads==1 instead of asserting on intermediate state

In `it_should_persist_the_number_of_completed_peers_for_each_torrent_into_the_database`,
the retry loop previously asserted `swarm_metadata.downloads() == 1` on the
first observation. If the background event listener has stored the row but
not yet updated the in-memory `downloads` counter, that assertion would
panic the test instead of letting the bounded `tokio::time::timeout` wait
for the desired state.

Change the check to `if downloads() == 1 { break true }` so the timeout
actually governs the wait and intermediate observations are tolerated.

Addresses Copilot review comment #17 on PR #1718.

Author: josecelano

packages/tracker-core/tests/integration.rs

@@ -80,7 +80,10 @@ async fn it_should_persist_the_number_of_completed_peers_for_each_torrent_into_t
     // Load torrents from the database to ensure the completed stats are persisted.
     // Bound the wait with a timeout instead of a fixed iteration count so the
     // test fails loudly on a stalled system rather than after an arbitrary
-    // number of immediate retries.
+    // number of immediate retries. Re-check the desired state (`downloads == 1`)
+    // inside the retry condition so an intermediate observation does not
+    // panic the test before the background listener has finished applying
+    // the persisted value.
     let restored = tokio::time::timeout(std::time::Duration::from_secs(5), async {
         loop {
             test_env
@@ -91,8 +94,9 @@ async fn it_should_persist_the_number_of_completed_peers_for_each_torrent_into_t
                 .unwrap();
 
             if let Some(swarm_metadata) = test_env.get_swarm_metadata(&info_hash).await {
-                assert!(swarm_metadata.downloads() == 1);
-                break true;
+                if swarm_metadata.downloads() == 1 {
+                    break true;
+                }
             }
 
             tokio::time::sleep(std::time::Duration::from_millis(50)).await;