test(ui): read notification colors from app theme

HANDOFF.md

@@ -11,18 +11,20 @@
   the Shape block; focused test passes. This task is ready to commit.
 - `GeometryFieldWidthTests` now identifies the shared draggable-layer Geometry block; focused test
   passes. This task is ready to commit.
-- Clean app build is 0 warnings. Full suite: 9 failed / 513 passed of 522; remaining failures are
+- `NotificationServiceTests` now run tint assertions with the real theme resources and expect the
+  current `Brush.ErrorContainer` token; all 8 tests in that class pass. This task is ready to commit.
+- Clean app build is 0 warnings. Full suite: 5 failed / 517 passed of 522; remaining failures are
   being handled one task and one local commit at a time.
 
 ## Next action
 
-Commit the Geometry selector update, then take the next remaining failure. Do not
-push absent a milestone/checkpoint request.
+Commit the notification tint test fix, then take the next remaining failure. Do not push absent a
+milestone/checkpoint request.
 
 ## Landmines
 
 - Build/test with Windows `dotnet.exe`; the full suite can hang in WASAPI teardown.
-- `verify.sh` cannot pass until the remaining 9 suite failures are resolved; scope checks are run
+- `verify.sh` cannot pass until the remaining 5 suite failures are resolved; scope checks are run
   separately when that gate exits early.
 - Any integration test constructing `MainWindow` must set `LayoutPathOverride` to a temporary DB
   and clear it in `finally`.

ytLive.Tests/NotificationServiceTests.cs

@@ -11,8 +11,13 @@ namespace ytLive.Tests;
 /// Errors must never auto-expire (sticky until dismissed); the rest get short
 /// lifetimes; everything routes to the in-window ToastArea.
 /// </summary>
+[Collection("RealApp")]
 public class NotificationServiceTests
 {
+    private readonly RealAppHost _app;
+
+    public NotificationServiceTests(RealAppHost app) => _app = app;
+
     [Theory]
     [InlineData(AppNotificationSeverity.Info, 4)]
     [InlineData(AppNotificationSeverity.Success, 4)]
@@ -39,11 +44,14 @@ public class NotificationServiceTests
     [InlineData(AppNotificationSeverity.Info, "#3a3b52")]
     [InlineData(AppNotificationSeverity.Success, "#1d5c38")]
     [InlineData(AppNotificationSeverity.Warning, "#b8860b")]
-    [InlineData(AppNotificationSeverity.Error, "#8f1f1f")]
+    [InlineData(AppNotificationSeverity.Error, "#93000a")]
     public void Severities_Map_To_Dark_Card_Tints(AppNotificationSeverity severity, string expectedHex)
     {
-        var request = NotificationService.BuildRequest("Title", "Body", severity);
+        _app.Run(() =>
+        {
+            var request = NotificationService.BuildRequest("Title", "Body", severity);
 
-        Assert.Equal(expectedHex.ToLowerInvariant()[^6..], request.BackgroundColor!.Value.ToHex().ToLowerInvariant()[^6..]);
+            Assert.Equal(expectedHex.ToLowerInvariant()[^6..], request.BackgroundColor!.Value.ToHex().ToLowerInvariant()[^6..]);
+        });
     }
 }