fix(ui): preserve cropped chat and button faces

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

@@ -232,6 +232,7 @@ public sealed class ChatWindowController
             float oldTop = bar.Top;
             bar.Top    = 0f;                       // pull up to the panel top (resize-bar reclaim)
             bar.Height = bar.Height + oldTop;
+            bar.ResetAnchorCapture();
             bar.Model         = c.Transcript.Scroll;
             bar.SpriteResolve = resolve;
             bar.TrackSprite    = TrackSprite;
@@ -308,6 +309,7 @@ public sealed class ChatWindowController
             // just LEFT of the scrollbar column — shift it one button-width left.
             if (track is not null)
                 maxMinEl.Left = track.Left - maxMinEl.Width;
+            maxMinEl.ResetAnchorCapture();
             maxMinEl.OnClick = c.ToggleMaximize;
         }
 

src/AcDream.App/UI/UiButton.cs

@@ -151,9 +151,10 @@ public sealed class UiButton : UiElement, IUiGlobalTimeListener, IUiDatStateful
         _resolve = resolve;
         ClickThrough = false;   // buttons are interactive — opt OUT of click-through
 
-        foreach (uint stateId in info.States.Keys)
-            if (stateId != UiStateInfo.DirectStateId)
-                _availableStates.Add(stateId);
+        // Visual transitions can select only states with an actual button face.
+        // Retail layouts commonly declare an empty Normal_pressed descriptor while
+        // supplying art only for Normal/Highlight. Treating that property-only state
+        // as drawable briefly blanks the button during mouse-down.
         foreach (string stateName in info.StateMedia.Keys)
             if (UiButtonStateMachine.TryStateId(stateName, out uint stateId))
                 _availableStates.Add(stateId);

src/AcDream.App/UI/UiElement.cs

@@ -483,11 +483,41 @@ public abstract class UiElement
         Left = x; Top = y; Width = w; Height = h;
     }
 
-    /// <summary>Forget the captured anchor margins so the next <see cref="ApplyAnchor"/>
-    /// re-captures them from the CURRENT rect. Call after manually repositioning/resizing
-    /// an anchored element at runtime (e.g. reflowing the chat input when the channel
-    /// button width changes) so the new rect becomes the anchor baseline.</summary>
-    internal void ResetAnchorCapture() => _anchorCaptured = false;
+    /// <summary>
+    /// Make the current geometry the new layout baseline after an intentional
+    /// controller/runtime change. Compatibility anchors recapture their margins on
+    /// the next layout pass; imported raw-edge policies rebase immediately against
+    /// the current parent rect.
+    /// </summary>
+    internal void ResetAnchorCapture()
+    {
+        _anchorCaptured = false;
+        if (LayoutPolicy is null || Parent is null) return;
+
+        LayoutPolicy.Rebase(
+            UiPixelRect.FromPositionAndSize(
+                (int)Left,
+                (int)Top,
+                (int)Width,
+                (int)Height),
+            UiPixelRect.FromPositionAndSize(
+                0,
+                0,
+                (int)Parent.Width,
+                (int)Parent.Height));
+    }
+
+    /// <summary>
+    /// Rebase each immediate child after a host deliberately changes this element's
+    /// design extent. This is used when a production DAT root contains auxiliary
+    /// space that is cropped by its retail window mount; descendants must reflow
+    /// from the mounted content rect, not from the uncropped LayoutDesc display box.
+    /// </summary>
+    internal void RebaseChildLayoutBaselines()
+    {
+        foreach (var child in _children)
+            child.ResetAnchorCapture();
+    }
 
     /// <summary>Walk up to the owning <see cref="UiRoot"/> (the top of the tree), or null
     /// if this element is not attached. Lets a widget reach focus/capture services — e.g.