fix(runtime,ui): Campaign LA gate round 2 — world name reads durably; dialogs center on the canvas

Two live-integration gaps the ef96c554 unit tests could not see:

1. World box stayed empty against ACE: ServerName (0xF7E1) arrives in the
   SAME connect batch as CharacterList, so ServerNameReceived fires during
   the handshake pump BEFORE the controller binding subscribes - the
   event-only wiring proved the state and controller but never the live
   ordering. StartCore now reads the durable WorldSession.ServerInfo after
   connect exactly like the roster (ILiveSessionOperations.GetServerInfo,
   default interface method so no fake breaks); the event remains for
   post-connect updates. Pinned by a Start-level test.

2. The exit confirmation rendered far right of the screen: all three
   retail dialog views centered against the raw window size while the
   active screen lays out in the fixed 800x600 canvas - center-of-1920
   is canvas-760, which the stretch pushes off-center. Views now center
   against UiRoot.EffectiveCanvasSize (canvas while a pre-world screen is
   active, window otherwise). Pinned by growing the window over the fixed
   canvas in the exit-dialog test and asserting the scrim spans the canvas
   with the popup centered at 400.

Runtime 1666, App 5100+6 skips, green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/AcDream.App/UI/Layout/RetailConfirmationDialogView.cs

@@ -129,10 +129,15 @@ internal sealed class RetailConfirmationDialogView : IRetailDialogView
 
     private void SizeAndCenter()
     {
+        // Center against the space the tree lays out in — the fixed authored
+        // canvas while a pre-world screen is active (gate round 2: centering
+        // against the raw window width put the exit dialog far right of the
+        // stretched 800x600 canvas center).
+        var space = _host.EffectiveCanvasSize;
         Root.Left = 0f;
         Root.Top = 0f;
-        Root.Width = _host.Width;
-        Root.Height = _host.Height;
+        Root.Width = space.X;
+        Root.Height = space.Y;
         _popup.Left = MathF.Round((Root.Width - _popup.Width) * 0.5f);
         _popup.Top = MathF.Round((Root.Height - _popup.Height) * 0.5f);
     }

src/AcDream.App/UI/Layout/RetailConfirmationTextInputDialogView.cs

@@ -150,10 +150,13 @@ internal sealed class RetailConfirmationTextInputDialogView : IRetailDialogView
 
     private void SizeAndCenter()
     {
+        // Center against the layout space (fixed canvas while a pre-world
+        // screen is active) — see RetailConfirmationDialogView.SizeAndCenter.
+        var space = _host.EffectiveCanvasSize;
         Root.Left = 0f;
         Root.Top = 0f;
-        Root.Width = _host.Width;
-        Root.Height = _host.Height;
+        Root.Width = space.X;
+        Root.Height = space.Y;
         _popup.Left = MathF.Round((Root.Width - _popup.Width) * 0.5f);
         _popup.Top = MathF.Round((Root.Height - _popup.Height) * 0.5f);
     }

src/AcDream.App/UI/Layout/RetailMessageDialogView.cs

@@ -95,10 +95,13 @@ internal sealed class RetailMessageDialogView : IRetailDialogView
 
     private void SizeAndCenter()
     {
+        // Center against the layout space (fixed canvas while a pre-world
+        // screen is active) — see RetailConfirmationDialogView.SizeAndCenter.
+        var space = _host.EffectiveCanvasSize;
         Root.Left = 0f;
         Root.Top = 0f;
-        Root.Width = _host.Width;
-        Root.Height = _host.Height;
+        Root.Width = space.X;
+        Root.Height = space.Y;
         _popup.Left = MathF.Round((Root.Width - _popup.Width) * 0.5f);
         _popup.Top = MathF.Round((Root.Height - _popup.Height) * 0.5f);
     }

src/AcDream.App/UI/UiRoot.cs

@@ -44,6 +44,19 @@ public sealed class UiRoot : UiElement
     /// </summary>
     public Vector2? FixedCanvasSize { get; set; }
 
+    /// <summary>
+    /// The coordinate space the retained tree currently lays out in: the fixed
+    /// authored canvas while one is active, else the window itself. Anything
+    /// that positions against "the screen" (dialog centering, full-screen
+    /// scrims) must use THIS — the gate-round-2 exit dialog centered against
+    /// the 1920px window while the tree lived in the 800px canvas, landing far
+    /// right of the visible screen center.
+    /// </summary>
+    public Vector2 EffectiveCanvasSize =>
+        FixedCanvasSize is { X: > 0f, Y: > 0f } canvas
+            ? canvas
+            : new Vector2(Width, Height);
+
     /// <summary>Window→canvas stretch factor; One when no fixed canvas is set.</summary>
     public Vector2 CanvasScale =>
         FixedCanvasSize is { X: > 0f, Y: > 0f } canvas && Width > 0f && Height > 0f

src/AcDream.Runtime/Session/LiveSessionController.cs

@@ -172,6 +172,16 @@ public interface ILiveSessionOperations
     WorldSession CreateSession(IPEndPoint endpoint);
     void Connect(WorldSession session, string user, string password);
     CharacterList.Parsed? GetCharacters(WorldSession session);
+    /// <summary>
+    /// Campaign LA gate round 2 (world-name live fix): ACE sends ServerName
+    /// (0xF7E1) in the SAME connect-response batch as CharacterList, so the
+    /// <c>ServerNameReceived</c> event fires during the handshake pump —
+    /// BEFORE the controller's binding subscribes. The durable
+    /// <see cref="WorldSession.ServerInfo"/> field is therefore read
+    /// synchronously after Connect, exactly like <see cref="GetCharacters"/>
+    /// reads the durable roster; the event remains for post-connect updates.
+    /// </summary>
+    ServerName.Parsed? GetServerInfo(WorldSession session) => session.ServerInfo;
     void StartCharacterSelectionReceive(WorldSession session) =>
         session.StartCharacterSelectionReceive();
     void EnterWorld(WorldSession session, int activeCharacterIndex);
@@ -753,6 +763,14 @@ public sealed class LiveSessionController
                     return new LiveSessionStartResult(LiveSessionStartStatus.Deferred);
             }
 
+            // World name arrives in the SAME connect batch as CharacterList,
+            // during the handshake pump — before the binding's
+            // ServerNameReceived subscription exists — so the durable field is
+            // read here exactly like the roster above (gate-round-2 live fix:
+            // the event-only wiring left the World box empty against ACE).
+            if (_operations.GetServerInfo(session) is { } serverInfo)
+                CharacterSelectionState.ApplyWorldName(serverInfo.WorldName);
+
             // Campaign LA slice LA2: the probe short-circuit lands here —
             // only after a real CharacterList was returned and its roster was
             // reported, before TrySelectCharacter ever runs. A missing

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

@@ -386,6 +386,13 @@ public sealed class CharacterManagementUiControllerTests
         UiButton exit = environment.Button(
             CharacterManagementUiController.ExitElementId);
 
+        // Gate round 2 follow-up: the window is BIGGER than the fixed canvas
+        // (the live shape — 1920×1080 window over the 800×600 authored
+        // screen). The exit dialog centered against the raw window width and
+        // landed far right of the visible canvas center.
+        environment.Host.Width = 1920f;
+        environment.Host.Height = 1080f;
+
         exit.OnClick!();
 
         Assert.NotEqual(0u, controller.ConfirmExitDialogContext);
@@ -393,6 +400,14 @@ public sealed class CharacterManagementUiControllerTests
         Assert.Equal(
             "Are you sure you want to leave?",
             Message(dialog));
+        // The dialog's scrim + popup must live in CANVAS space: scrim spans
+        // exactly the canvas, popup centers within it.
+        Assert.Equal(800f, dialog.Root.Width);
+        Assert.Equal(600f, dialog.Root.Height);
+        UiElement popup = Assert.Single(
+            dialog.Root.Children,
+            static child => child.Visible && child.Width > 0f);
+        Assert.InRange(popup.Left + popup.Width * 0.5f, 399f, 401f);
         DialogButton(dialog, RetailConfirmationDialogView.RejectButtonId).OnClick!();
 
         Assert.Equal(0, environment.Runtime.RequestExitCalls);

tests/AcDream.Runtime.Tests/Session/LiveSessionControllerTests.cs

@@ -113,6 +113,13 @@ public sealed class LiveSessionControllerTests
             return Characters;
         }
 
+        /// <summary>Gate-round-2 world-name live fix: mirrors the durable
+        /// post-connect read the production path performs (the wire event
+        /// fires during the handshake, before any subscriber exists).</summary>
+        public ServerName.Parsed? ServerInfo { get; set; }
+
+        public ServerName.Parsed? GetServerInfo(WorldSession session) => ServerInfo;
+
         public void StartCharacterSelectionReceive(WorldSession session) =>
             calls.Add("start-character-selection-receive");
 
@@ -349,6 +356,33 @@ public sealed class LiveSessionControllerTests
         Assert.True(host.CommandBuses[0].Active);
     }
 
+    /// <summary>
+    /// Gate-round-2 live fix: ACE sends ServerName (0xF7E1) in the SAME
+    /// connect batch as CharacterList, so the event fires during the
+    /// handshake pump before the binding subscribes — the World box stayed
+    /// empty against a live server while the event-only unit tests passed.
+    /// Start must read the durable ServerInfo after connect, exactly like
+    /// the roster.
+    /// </summary>
+    [Fact]
+    public void Start_AppliesWorldNameFromDurableServerInfoAfterConnect()
+    {
+        var calls = new List<string>();
+        var operations = new TestOperations(calls)
+        {
+            ServerInfo = new ServerName.Parsed(1, 128, "sawato"),
+        };
+        var host = new TestHost(calls);
+        var controller = new LiveSessionController(operations);
+
+        LiveSessionStartResult result = controller.Start(LiveOptions(), host);
+
+        Assert.Equal(LiveSessionStartStatus.Connected, result.Status);
+        Assert.Equal(
+            "sawato",
+            controller.CharacterSelectionState.View.Snapshot.WorldName);
+    }
+
     [Fact]
     public void Start_ReportsRosterFromCharacterListBeforeSelection()
     {