fix #430: tooltip wrap and draw honor the text child's authored margins

Third owner-screenshot round: acdream fit one more word per line than
retail and drew glyphs flush against the popup's right border. Retail's
InqSizewMargins @0x00469660 wraps the glyph list at
(bound - m_margL - m_margR) and adds the margins back into the measured
width; the popup skins' shared text child 0x10000396 authors margins
L=2/R=2 (U=2/D=2 on three of the four skins — live-DAT probed). The
presenter now subtracts the horizontal margins from both wrap passes,
re-adds them into the measured width used for root sizing, and counts
the vertical margins in the measured/re-wrapped heights; the widget's
own draw already insets by all four margins (UiText ContentOffsetX +
the top/bottom inset), so the right-side spacing returns for free.

TooltipSkinLiveDatTests pins the authored margins per skin alongside
the P0x3D=256 wrap bound; a new presenter test proves margins shrink
the wrap bound and survive onto the widget.

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

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

@@ -510,7 +510,52 @@ public sealed class RetailTooltipPresenterTests
             $"popup height {popup.Height} does not fit {lines.Count} lines");
     }
 
-    private static void HoverAndDwellWithClampedPopup(UiRoot root, int maxWidth)
+    [Fact]
+    public void AuthoredMargins_ShrinkTheWrapBound_AndInsetTheMeasuredWidth()
+    {
+        // The real skins' text child (0x10000396) authors margins L=2/R=2
+        // (U=2/D=2 on three of four skins). Retail's InqSizewMargins
+        // @0x00469660 wraps at (bound − margL − margR) and adds the margins
+        // back into the measured width; without this, line one fit one more
+        // word than retail and the glyphs drew flush against the popup's
+        // right border (CA5 owner screenshot pair, 2026-08-24).
+        var (root, _, _) = CreateHarness();
+        string longText = string.Join(
+            " ", Enumerable.Repeat("description", 40));
+        var target = new HoverTarget
+        {
+            Left = 100, Top = 100, Width = 40, Height = 20,
+            AuthoredTooltipEnabled = true,
+            AuthoredTooltipText = longText,
+            AuthoredTooltipRootElementId = PopupRootId,
+            AuthoredTooltipLayoutDid = PopupLayoutDid,
+        };
+        root.AddChild(target);
+
+        // Wide horizontal margins make the difference unmissable at the
+        // 8px-per-char test measure: the wrap bound is 200−80=120.
+        HoverAndDwellWithClampedPopup(root, maxWidth: 200, marginX: 40, marginY: 8);
+
+        var text = FindText(root.Children[^1]);
+        Assert.NotNull(text);
+        var lines = text!.LinesProvider();
+        Assert.True(lines.Count >= 3, $"expected >=3 wrapped lines, got {lines.Count}");
+        // Glyphs wrap INSIDE the margins...
+        Assert.All(lines, l => Assert.True(
+            l.Text.Length * 8f <= 200f - 80f + 8f,
+            $"line ignored the margins: {l.Text}"));
+        // ...and the widget keeps the margins so the draw insets by them
+        // (the right-side spacing the owner's retail screenshot shows).
+        Assert.Equal(40f, text.MarginLeft);
+        Assert.Equal(40f, text.MarginRight);
+        // Height accounts for the vertical margins on top of the lines.
+        float lineHeight = 14f;
+        Assert.True(root.Children[^1].Height >= lines.Count * lineHeight + 16f,
+            $"popup height {root.Children[^1].Height} lost the vertical margins");
+    }
+
+    private static void HoverAndDwellWithClampedPopup(
+        UiRoot root, int maxWidth, int marginX = 0, int marginY = 0)
     {
         // The REAL skins bound the wrap on the TEXT CHILD: 0x10000396
         // authors P0x3D=256 on all four popup skins (live-DAT probed
@@ -520,7 +565,16 @@ public sealed class RetailTooltipPresenterTests
         {
             ImportedLayout layout = BuildPopup();
             if (layout.FindElement(TextChildId) is { } textChild)
+            {
                 textChild.AuthoredResizeMaxWidth = maxWidth;
+                if (textChild is UiText t)
+                {
+                    t.MarginLeft = marginX;
+                    t.MarginRight = marginX;
+                    t.MarginTop = marginY;
+                    t.MarginBottom = marginY;
+                }
+            }
             return layout;
         });
         HoverAndDwell(root);

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

@@ -29,16 +29,26 @@ public sealed class TooltipSkinLiveDatTests
         Assert.NotNull(tree);
 
         int textChildren = 0;
-        void Walk(ElementInfo e)
+        void Walk(ElementInfo e, uint parentId)
         {
             if (e.Id == 0x10000396u && e.Type == 12)
             {
                 textChildren++;
                 Assert.Equal(256, e.MaxWidth);
+                // Retail wraps at (256 - margL - margR) and draws inset by
+                // the margins — the CA5 owner-screenshot delta (one extra
+                // word on line one + text flush against the right border).
+                // All four skins author L=2/R=2; skin 0x10000398 alone
+                // authors no vertical margins (live-DAT probe 2026-08-24).
+                Assert.Equal(2, e.MarginLeft);
+                Assert.Equal(2, e.MarginRight);
+                int vertical = parentId == 0x10000398u ? 0 : 2;
+                Assert.Equal(vertical, e.MarginTop);
+                Assert.Equal(vertical, e.MarginBottom);
             }
-            foreach (var c in e.Children) Walk(c);
+            foreach (var c in e.Children) Walk(c, e.Id);
         }
-        Walk(tree!);
+        Walk(tree!, 0);
         Assert.True(textChildren >= 4,
             $"expected the text child under all four popup skins, found {textChildren}");
     }