feat(notification-outbox): add NotificationOutboxOptions and delivery adapter abstraction

tests/ScadaLink.NotificationOutbox.Tests/Delivery/DeliveryOutcomeTests.cs

@@ -0,0 +1,36 @@
+using ScadaLink.NotificationOutbox.Delivery;
+
+namespace ScadaLink.NotificationOutbox.Tests.Delivery;
+
+public class DeliveryOutcomeTests
+{
+    [Fact]
+    public void Success_SetsResolvedTargets_AndNoError()
+    {
+        var outcome = DeliveryOutcome.Success("targets");
+
+        Assert.Equal(DeliveryResult.Success, outcome.Result);
+        Assert.Equal("targets", outcome.ResolvedTargets);
+        Assert.Null(outcome.Error);
+    }
+
+    [Fact]
+    public void Transient_SetsError_AndNoResolvedTargets()
+    {
+        var outcome = DeliveryOutcome.Transient("e");
+
+        Assert.Equal(DeliveryResult.TransientFailure, outcome.Result);
+        Assert.Equal("e", outcome.Error);
+        Assert.Null(outcome.ResolvedTargets);
+    }
+
+    [Fact]
+    public void Permanent_SetsError_AndNoResolvedTargets()
+    {
+        var outcome = DeliveryOutcome.Permanent("e");
+
+        Assert.Equal(DeliveryResult.PermanentFailure, outcome.Result);
+        Assert.Equal("e", outcome.Error);
+        Assert.Null(outcome.ResolvedTargets);
+    }
+}

tests/ScadaLink.NotificationOutbox.Tests/NotificationOutboxOptionsTests.cs

@@ -0,0 +1,17 @@
+namespace ScadaLink.NotificationOutbox.Tests;
+
+public class NotificationOutboxOptionsTests
+{
+    [Fact]
+    public void Defaults_AreExpectedValues()
+    {
+        var options = new NotificationOutboxOptions();
+
+        Assert.Equal(TimeSpan.FromSeconds(10), options.DispatchInterval);
+        Assert.Equal(100, options.DispatchBatchSize);
+        Assert.Equal(TimeSpan.FromMinutes(10), options.StuckAgeThreshold);
+        Assert.Equal(TimeSpan.FromDays(365), options.TerminalRetention);
+        Assert.Equal(TimeSpan.FromDays(1), options.PurgeInterval);
+        Assert.Equal(TimeSpan.FromMinutes(1), options.DeliveredKpiWindow);
+    }
+}