test: deflake flush-loop and retry tests

tests/Trax.Effect.Tests.Broadcaster/UnitTests/TrainEventReceiverServiceTests.cs

@@ -265,12 +265,18 @@ public async Task ConnectionFailure_RetriesInsteadOfCrashing()
             });
 
         var service = CreateService();
-        using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(10));
+        using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(20));
 
         await service.StartAsync(cts.Token);
 
-        // The initial retry delay is 5s — wait long enough for at least one retry
-        await Task.Delay(TimeSpan.FromSeconds(7));
+        // The initial retry delay is 5s, so a second StartAsync invocation
+        // should land within ~5-6s of the first. Poll for the actual second
+        // call instead of sleeping a fixed window: the test then reflects the
+        // service's real retry timing rather than racing GitHub Actions
+        // scheduling overhead.
+        var deadline = DateTime.UtcNow + TimeSpan.FromSeconds(15);
+        while (DateTime.UtcNow < deadline && callCount <= 1)
+            await Task.Delay(100);
 
         // Should not have crashed the host — service retries
         callCount.Should().BeGreaterThan(1, "the service should retry after connection failure");

tests/Trax.Effect.Tests.Integration/UnitTests/Services/DataContextLoggingProviderTests.cs

@@ -192,8 +192,23 @@ public async Task FlushLoop_BatchesLogsToDatabase()
         for (var i = 0; i < 5; i++)
             logger.Log(LogLevel.Information, default, i, null, (s, _) => $"msg {s}");
 
-        // Wait for the 1-second flush timer to tick once.
-        await Task.Delay(1500);
+        // Poll for the flush loop to land at least one batch instead of waiting
+        // a fixed window past the 1-second timer tick. CI scheduling can stretch
+        // the timer's wakeup well past 1.5s; once any log is persisted we know
+        // the flush path is working and can stop waiting.
+        var deadline = DateTime.UtcNow + TimeSpan.FromSeconds(15);
+        var landed = 0;
+        while (DateTime.UtcNow < deadline)
+        {
+            context.Reset();
+            landed = await context
+                .Logs.AsNoTracking()
+                .Where(l => l.Category == "TestCategory")
+                .CountAsync();
+            if (landed >= 1)
+                break;
+            await Task.Delay(50);
+        }
         provider.Dispose();
 
         context.Reset();