refactor(settings): a pull-out drawer, with Zoom as a category — and the menu moves to the wordmark

Creator directive, 2026-11-01. Settings stopped being a centred modal.

- **Drawer** (Controls/SettingsDrawer): hosted in PreviewPane's pull-out stack, 320px, the same
  animated-width pattern as Stream Settings / YPP / Socials / TEST, opened by the gear rail tab
  on a single left click. SettingsDrawerOpen is exclusive with the other four, both directions.
  This also removes the modal's MaxHeight-700 scroll problem for good: the drawer is the height
  of the preview.
- **Categories**: headings with controls indented beneath them. Zoom now owns *Zoom view shape*
  (Circle / Phone / Tablet) and *Zoom box follows*; Recordings, Brand logo and Scene transition
  are their own categories.
- **The app menu moved to the LlamaCasty wordmark** (right-click → Report Bug / Feature Request /
  About). Left-click still opens About. The gear tab no longer carries a menu at all, so clicking
  it does exactly one thing.

OverlayHost keeps only the Bug / Feature / About panels; its brand-logo handlers and the dev-panel
injection moved with the settings block. BrandLogoPreviewTests follows the control (same assertions,
new path). Release 0 warnings; 15 tests pass across brand logo, zoom, entitlement and preview
history.

ViewModels/MainViewModel.Settings.cs

@@ -0,0 +1,42 @@
+namespace ytLive.ViewModels;
+
+/// <summary>
+/// App Settings as a right-edge drawer (creator ruling 2026-11-01): the gear rail tab opens it
+/// immediately, in the same exclusive-slide pattern as Stream Settings / YPP / Socials / TEST.
+///
+/// <para>It is a separate flag from <see cref="IsSettingsOpen"/> because the overlay shell now
+/// only carries Report Bug / Feature Request / About — settings stopped being a modal.</para>
+/// </summary>
+public partial class MainViewModel
+{
+    private bool _settingsDrawerOpen;
+
+    public bool SettingsDrawerOpen
+    {
+        get => _settingsDrawerOpen;
+        private set => SetProperty(ref _settingsDrawerOpen, value);
+    }
+
+    internal void ToggleSettingsDrawer()
+    {
+        if (_settingsDrawerOpen)
+        {
+            SettingsDrawerOpen = false;
+            return;
+        }
+
+        // One drawer at a time, like the rail's other tabs.
+        BroadcastForm.IsDrawerOpen = false;
+        Ypp.IsDrawerOpen = false;
+        TestSession.IsDrawerOpen = false;
+        if (SocialsDrawerOpen) CloseSocialsDrawer();
+
+        SettingsDrawerOpen = true;
+    }
+
+    /// <summary>Called by the other drawers when they open, so settings yields to them.</summary>
+    private void CloseSettingsDrawerIfOpen()
+    {
+        if (_settingsDrawerOpen) SettingsDrawerOpen = false;
+    }
+}