feat(top bar): EDIT moves beside the gear; the gear wears the app's orange

- EDIT leaves the centre session cluster and sits immediately right of the gear, in the brand
  column — so mode lives with the controls that configure the app, not with the session buttons.
- The gear is a LlamaCasty control, so its icon is `attention` orange instead of muted grey.

Guard: UiShellTests asserts the gear fill and that EDIT appears before the centre (session)
cluster, so a later reformat cannot quietly put it back.

ytLive.Tests/UiShellTests.cs

@@ -74,6 +74,22 @@ public class UiShellTests
         Assert.Contains("return;", preview);
     }
 
+    [Fact]
+    public void Edit_sits_beside_the_orange_gear()
+    {
+        var topBar = SourceAssert.Text("Controls", "TopBar.xaml");
+
+        // The gear is a LlamaCasty control, so it wears the app's orange (not a muted icon grey).
+        Assert.Contains("Fill=\"{StaticResource Brush.Attention}\" Width=\"18\" Height=\"18\"", topBar);
+
+        // EDIT lives in the LEFT cluster, immediately after the gear — not in the centre session
+        // cluster (creator ruling 2026-10-30).
+        var edit = topBar.IndexOf("EditingActive", System.StringComparison.Ordinal);
+        var centre = topBar.IndexOf("Grid.Column=\"1\"", System.StringComparison.Ordinal);
+        Assert.True(edit > 0 && centre > edit,
+            "the EDIT toggle must appear before the centre (session) cluster");
+    }
+
     private static int Count(string haystack, string needle)
     {
         var hits = 0;