feat: port retail magic lifecycle and retained spell UI

Complete the retail cast-intent, target, component, enchantment, and busy-state paths; mount the DAT-authored spell bar, spellbook, component book, effects panels, and shared panel lifecycle; and add scoped input plus conformance coverage.

Co-Authored-By: Codex <noreply@openai.com>

tests/AcDream.App.Tests/UI/Layout/SpellcastingUiControllerTests.cs

@@ -0,0 +1,173 @@
+using AcDream.App.Spells;
+using AcDream.App.UI;
+using AcDream.App.UI.Layout;
+using AcDream.Core.Items;
+using AcDream.Core.Selection;
+using AcDream.Core.Spells;
+
+namespace AcDream.App.Tests.UI.Layout;
+
+public sealed class SpellcastingUiControllerTests
+{
+    private static (uint, int, int) NoTex(uint _) => (0u, 0, 0);
+
+    [Fact]
+    public void ImportedFixture_BindsAllTabs_AndTracksEquippedEndowment()
+    {
+        ImportedLayout layout = LayoutImporter.Build(
+            FixtureLoader.LoadCombatInfos(), NoTex, datFont: null);
+        var spellbook = new Spellbook();
+        var objects = new ClientObjectTable();
+        objects.AddOrUpdate(new ClientObject { ObjectId = 1u, Name = "Player" });
+        var used = new List<uint>();
+        using SpellcastingUiController? controller = Bind(
+            layout, spellbook, objects, used.Add);
+
+        Assert.True(controller is not null, DescribeBinding(layout));
+        objects.AddOrUpdate(new ClientObject
+        {
+            ObjectId = 2u,
+            Name = "Orb",
+            Type = ItemType.Caster,
+            WielderId = 1u,
+            CurrentlyEquippedLocation = EquipMask.Held,
+            SpellId = 2670u,
+            IconId = 0x06001234u,
+        });
+        controller.Tick();
+
+        UiElement host = Assert.IsAssignableFrom<UiElement>(
+            layout.FindElement(SpellcastingUiController.EndowmentId));
+        Assert.True(host.Visible);
+        UiCatalogSlot slot = Assert.IsType<UiCatalogSlot>(host.Children[^1]);
+        Assert.Equal(2u, slot.EntryId);
+        Assert.Equal(2670u, slot.CatalogIconTexture);
+        Assert.Equal(2u, slot.CatalogOverlayTexture);
+
+        slot.OnEvent(new UiEvent(0, slot, UiEventType.Click));
+        var cast = Assert.IsType<UiButton>(
+            layout.FindElement(SpellcastingUiController.CastButtonId));
+        cast.OnEvent(new UiEvent(0, cast, UiEventType.Click));
+        Assert.Equal([2u], used);
+    }
+
+    [Fact]
+    public void FavoriteDrop_IgnoresForeignInventoryPayload()
+    {
+        ImportedLayout layout = LayoutImporter.Build(
+            FixtureLoader.LoadCombatInfos(), NoTex, datFont: null);
+        var spellbook = new Spellbook();
+        spellbook.OnSpellLearned(42u, 1f);
+        spellbook.SetFavorite(0, 0, 42u);
+        var objects = new ClientObjectTable();
+        objects.AddOrUpdate(new ClientObject { ObjectId = 1u, Name = "Player" });
+        using SpellcastingUiController? controller = Bind(
+            layout, spellbook, objects, _ => { });
+
+        Assert.True(controller is not null, DescribeBinding(layout));
+        controller.Tick();
+        UiElement group = Assert.IsAssignableFrom<UiElement>(layout.FindElement(0x100000AAu));
+        UiItemList list = Descendants(group).OfType<UiItemList>().First();
+        UiCatalogSlot slot = Assert.IsType<UiCatalogSlot>(list.GetItem(0));
+        var foreign = new ItemDragPayload(9u, ItemDragSource.Inventory, 0, new UiItemSlot(), null);
+
+        bool handled = slot.OnEvent(new UiEvent(
+            0, slot, UiEventType.DropReleased, Payload: foreign));
+
+        Assert.True(handled);
+        Assert.Equal([42u], spellbook.GetFavorites(0));
+    }
+
+    [Fact]
+    public void UnrelatedObjectUpdate_DoesNotRecreateFavoriteSlots()
+    {
+        ImportedLayout layout = LayoutImporter.Build(
+            FixtureLoader.LoadCombatInfos(), NoTex, datFont: null);
+        var spellbook = new Spellbook();
+        spellbook.OnSpellLearned(42u, 1f);
+        spellbook.SetFavorite(0, 0, 42u);
+        var objects = new ClientObjectTable();
+        objects.AddOrUpdate(new ClientObject { ObjectId = 1u, Name = "Player" });
+        using SpellcastingUiController controller = Bind(
+            layout, spellbook, objects, _ => { })!;
+        UiElement group = layout.FindElement(0x100000AAu)!;
+        UiItemList list = Descendants(group).OfType<UiItemList>().First();
+        UiItemSlot before = list.GetItem(0)!;
+
+        objects.AddOrUpdate(new ClientObject { ObjectId = 99u, Name = "Rock" });
+        controller.Tick();
+
+        Assert.Same(before, list.GetItem(0));
+    }
+
+    [Fact]
+    public void ObjectTableClear_RemovesEquippedEndowmentAndCannotUseStaleGuid()
+    {
+        ImportedLayout layout = LayoutImporter.Build(
+            FixtureLoader.LoadCombatInfos(), NoTex, datFont: null);
+        var spellbook = new Spellbook();
+        var objects = new ClientObjectTable();
+        objects.AddOrUpdate(new ClientObject { ObjectId = 1u, Name = "Player" });
+        objects.AddOrUpdate(new ClientObject
+        {
+            ObjectId = 2u,
+            Name = "Orb",
+            Type = ItemType.Caster,
+            WielderId = 1u,
+            CurrentlyEquippedLocation = EquipMask.Held,
+            SpellId = 2670u,
+        });
+        var used = new List<uint>();
+        using SpellcastingUiController controller = Bind(
+            layout, spellbook, objects, used.Add)!;
+        UiElement host = layout.FindElement(SpellcastingUiController.EndowmentId)!;
+        UiCatalogSlot slot = Assert.IsType<UiCatalogSlot>(host.Children[^1]);
+        slot.OnEvent(new UiEvent(0, slot, UiEventType.Click));
+
+        objects.Clear();
+        controller.Tick();
+
+        Assert.False(host.Visible);
+        Assert.Equal(0u, slot.EntryId);
+        slot.OnEvent(new UiEvent(0, slot, UiEventType.DoubleClick));
+        Assert.Empty(used);
+    }
+
+    private static SpellcastingUiController? Bind(
+        ImportedLayout layout,
+        Spellbook spellbook,
+        ClientObjectTable objects,
+        Action<uint> useItem)
+    {
+        var casting = new SpellCastingController(
+            spellbook, () => null, () => 1u, () => { }, _ => { }, (_, _) => { }, _ => { });
+        return SpellcastingUiController.Bind(
+            layout, spellbook, casting, objects, () => 1u,
+            spellId => spellId,
+            item => item.ObjectId,
+            useItem,
+            new SelectionState(),
+            (_, _, _) => { },
+            (_, _) => { });
+    }
+
+    private static IEnumerable<UiElement> Descendants(UiElement root)
+    {
+        foreach (UiElement child in root.Children)
+        {
+            yield return child;
+            foreach (UiElement nested in Descendants(child)) yield return nested;
+        }
+    }
+
+    private static string DescribeBinding(ImportedLayout layout)
+    {
+        uint[] ids =
+        [
+            SpellcastingUiController.CastButtonId, SpellcastingUiController.EndowmentId,
+            0x100000A3u, 0x100000AAu, 0x100005C2u, 0x100005C3u,
+        ];
+        return string.Join(", ", ids.Select(id =>
+            $"{id:X8}={layout.FindElement(id)?.GetType().Name ?? "missing"}"));
+    }
+}