fix(ui): talk button keeps authored 46x17; white authored captions + font for talk/Send

Owner report (2026-08-24, post gate-pass): the chat channel button was
bigger than retail and both its caption and the Send caption were warm
gold instead of retail's near-white.

Size: retail never resizes the talk button — HandleSelection
@0x004cd540 only swaps the caption string; the authored 46x17 element
stands, and the authored SHORT captions ('Gen', 'Fell', ...) fit it —
that is why retail abbreviates. Our content-widening reflow (grow the
button to its label, shift the input) was a compensation for the
now-retired invented long captions, measured with the wrong font on
top. Deleted; the authored row layout stands.

Color + font: the button caption child (0x10000015) and the Send
button (0x10000019) both author pure white text with their OWN FontDid
0x40000002 (live-DAT probed) — different from the transcript font,
which is the other half of why 'Chat' fits 46px. UiMenu gains a
ButtonDatFont for the caption (popup rows keep the menu font);
the controller reads both elements' authored FontColor/FontDid instead
of the invented (1,.92,.72) constants.

The old widening pin is rewritten to the retail contract; a new
conformance test pins authored width, white captions, and the authored
font DID being requested for both buttons.

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

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

@@ -368,8 +368,15 @@ public class ChatLayoutConformanceTests
         Assert.Equal(605f, inputBar.Width);
     }
 
+    /// <summary>
+    /// 2026-08-24 rewrite: this test used to pin the content-widening
+    /// reflow (button grown past 46px for the invented long captions).
+    /// Retail never resizes the talk button — the authored 46x17 stands
+    /// through selection changes AND layout passes, and the input keeps its
+    /// authored start (owner-reported "button too big" delta).
+    /// </summary>
     [Fact]
-    public void ChatFixture_ChannelCaptionWidth_SurvivesImportedLayoutPass()
+    public void ChatFixture_ChannelButton_KeepsAuthoredWidthThroughLayoutPass()
     {
         var infos = FixtureLoader.LoadChatInfos();
         var layout = LayoutImporter.Build(infos, NoTex, null);
@@ -384,13 +391,12 @@ public class ChatLayoutConformanceTests
             NoTex);
         Assert.NotNull(controller);
 
-        controller!.Menu.OnSelect!.Invoke(ChatChannelKind.General);
-        float fittedWidth = controller.Menu.Width;
+        float inputLeft = controller!.Input.Left;
+        controller.Menu.OnSelect!.Invoke(ChatChannelKind.General);
         controller.Menu.ApplyAnchor(controller.Menu.Parent!.Width, controller.Menu.Parent.Height);
 
-        Assert.True(fittedWidth > 46f);
-        Assert.Equal(fittedWidth, controller.Menu.Width);
-        Assert.Equal(controller.Menu.Left + fittedWidth, controller.Input.Left);
+        Assert.Equal(46f, controller.Menu.Width);
+        Assert.Equal(inputLeft, controller.Input.Left);
     }
 
     [Fact]
@@ -734,4 +740,41 @@ public class ChatLayoutConformanceTests
             ApplyLayoutPassLocal(child);
         }
     }
+
+    /// <summary>
+    /// 2026-08-24 owner report ("chat button too big; caption should be
+    /// whiter — same for Send"): retail keeps the AUTHORED 46x17 talk
+    /// button (HandleSelection @0x004cd540 never resizes it — the authored
+    /// SHORT captions fit, which is why retail abbreviates), and both the
+    /// button caption child (0x10000015) and the Send button (0x10000019)
+    /// author PURE WHITE text with their own FontDid 0x40000002. The
+    /// previous content-widening reflow and invented warm-gold labels are
+    /// retired.
+    /// </summary>
+    [Fact]
+    public void TalkButtonAndSend_KeepAuthoredSizeFontAndWhiteCaptions()
+    {
+        var infos = FixtureLoader.LoadChatInfos();
+        ImportedLayout layout = LayoutImporter.Build(infos, NoTex, null);
+        var requestedFonts = new List<uint>();
+        var controller = ChatWindowController.Bind(
+            infos, layout, new ChatVM(new ChatLog()), () => NullCommandBus.Instance,
+            new ChatWindowState(), null, null, NoTex,
+            resolveFont: did => { requestedFonts.Add(did); return null; });
+        Assert.NotNull(controller);
+
+        UiMenu menu = Assert.IsType<UiMenu>(layout.FindElement(0x10000014u));
+        // Authored 46x17 stands — no content widening.
+        Assert.Equal(46f, menu.Width);
+        menu.OnSelect!.Invoke(ChatChannelKind.General);
+        Assert.Equal(46f, menu.Width);
+        // Authored caption color: pure white.
+        Assert.Equal(new System.Numerics.Vector4(1f, 1f, 1f, 1f), menu.TextColor);
+
+        var send = Assert.IsType<UiButton>(layout.FindElement(0x10000019u));
+        Assert.Equal(new System.Numerics.Vector4(1f, 1f, 1f, 1f), send.LabelColor);
+
+        // Both caption fonts were requested from the authored FontDid.
+        Assert.Contains(0x40000002u, requestedFonts);
+    }
 }