feat(chat): retail text style — two-plane glyph outlines, authored SpewBox/chat styles

Campaign CH round 4, user-gate items 1+2. Root cause: retail ships a
second (background) glyph atlas per font, dilated 2px on every side,
plus two border-pixel scalars (Font.NumHorizontalBorderPixels/
NumVerticalBorderPixels) that acdream's font reader never read — so
even the pre-existing outline parameter drew almost nothing once
enabled. Landed together (either half alone is a no-op or a
regression):

- UiDatFont carries BorderX/BorderY from the DAT font resource.
- UiRenderContext.DrawStringDat inflates the background blit's source
  and destination rect by that margin and restructures into retail's
  exact two-pass whole-string outline-then-fill model
  (UIElement_Text::DrawSelf), plus the 8-neighbour +-1px fallback for
  fonts with no background atlas. Corrects the stale "property 0xd"
  comment to the real ids, 0x21 (Outline) / 0x22 (OutlineColor).
- LayoutDesc property 0x21/0x22 import (ElementInfo.Outline/
  OutlineColor, LayoutImporter.ReadState, ElementReader.Merge/
  ApplyCanonicalLegacyProjection, DatWidgetFactory.BuildText) so every
  authored-outline element across the DAT set is correct at once.
- SpewBox: RetailFontId corrected from a round-3 heuristic
  (0x40000025) to the actually-authored 0x40000001 (18px bold serif),
  Outline=true set on the controller's UiText. Fill colour stays the
  user-gate-round-1-pinned yellow — font atlases are alpha-only
  (PFID_A8), so there is no baked shading that could explain the
  screenshot's gold as anything other than the outline itself.
- Chat transcript: default fill now seeds from its authored
  ARGB(255,204,204,204) instead of an unrelated color-table slot
  (ChatTranscriptRenderer.BuildLines takes the transcript's own
  DefaultColor as a parameter); the 34-entry LogTextType table is
  untouched, and every existing CH1 conformance test stays green
  unmodified.

Regenerated the committed chat_2100006f.json fixture from the real
installed DAT, confirming end to end (not by missing-field default)
that the transcript carries no outline.

Tests: font-reader border fields + inflation math pinned against the
real DAT font, two-pass draw ordering/tint/inflation via a new
TextRenderer.DebugSpriteSegmentVerts test seam, property 0x21/0x22
import at both the ElementReader.Merge and StateDesc-property layers,
SpewBox font/outline, and the chat default-shade seed with the color
table proven untouched.

Full Release suite: 12,610 passed / 4 skipped / 0 failed
(AcDream.slnx, complete solution).

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

src/AcDream.App/Rendering/TextRenderer.cs

@@ -115,6 +115,31 @@ public sealed class TextRenderer : IDisposable
         }
     }
 
+    /// <summary>
+    /// Test-only: same submission-ordered segmentation as
+    /// <see cref="DebugSpriteSegments"/>, but exposing the FULL per-vertex float
+    /// buffer (8 floats/vertex: x,y,u,v,r,g,b,a — see <see cref="AppendQuad"/>,
+    /// 6 vertices/quad) instead of just texture/count/alpha. Needed by the
+    /// <c>UiRenderContext.DrawStringDat</c> two-pass outline/fill tests — proving
+    /// draw ORDER (outline segment before fill segment), TINT (RGB, not just
+    /// alpha), and the background-plane INFLATION (dest quad size + UV span)
+    /// all requires more than <see cref="DebugSpriteSegments"/> exposes.
+    /// <c>AcDream.App.Tests</c>-only via <c>InternalsVisibleTo</c>.
+    /// </summary>
+    internal IReadOnlyList<(uint Texture, IReadOnlyList<float> Verts)> DebugSpriteSegmentVerts
+    {
+        get
+        {
+            var result = new List<(uint, IReadOnlyList<float>)>(_segUsed);
+            for (int i = 0; i < _segUsed; i++)
+            {
+                SpriteSeg seg = _spriteSegs[i];
+                result.Add((seg.Texture, seg.Verts.ToArray()));
+            }
+            return result;
+        }
+    }
+
     /// <summary>
     /// Test-only snapshot of the current frame's queued NORMAL-layer BITMAP FONT
     /// text buffer (<see cref="DrawString"/>/<see cref="DrawStringClipped"/>,