fix tests. new product advisories enhancements

src/Concelier/__Tests/StellaOps.Concelier.WebService.Tests/ConcelierTimelineEndpointTests.cs

@@ -44,8 +44,18 @@ public class ConcelierTimelineEndpointTests : IClassFixture<ConcelierApplication
 
         var stream = await response.Content.ReadAsStreamAsync();
         using var reader = new StreamReader(stream);
-        var firstLine = await reader.ReadLineAsync();
-        firstLine.Should().NotBeNull();
-        firstLine!.Should().StartWith("event: ingest.update");
+        // The SSE stream may start with a retry directive; skip non-event lines.
+        string? line;
+        string? eventLine = null;
+        while ((line = await reader.ReadLineAsync()) is not null)
+        {
+            if (line.StartsWith("event:", StringComparison.Ordinal))
+            {
+                eventLine = line;
+                break;
+            }
+        }
+        eventLine.Should().NotBeNull();
+        eventLine!.Should().StartWith("event: ingest.update");
     }
 }