fix(chargen): Campaign CC gate round 1 Batch C — rich text + labels + backdrops

Commit 1/3: chargen-scoped, low blast-radius fixes.

- New DatRichText helper: escape-normalize + word-wrap + per-segment
  palette color, porting UIElement_Text::SetStringInfoWithFont /
  AppendStringInfoWithFont's composition model. Routes the Heritage
  (GF-2), Town (GF-11a), and Profession (GF-3) description boxes
  through it instead of a raw unwrapped single-Line LinesProvider.
  Heritage headers use font-color palette index 1 (green), bodies
  index 0 (white), matching AppendStringInfoWithFont's own font-index
  argument. Town's diagnosed GF-11a root cause: a single un-wrapped
  line meant the town-specific suffix rendered past the clipped
  viewport, so switching towns looked like "text never changes" even
  though the underlying composed string genuinely differed.

- GF-3: bind the Profession page's description textbox (0x100003e0,
  gmCGProfessionPage::InitializePage @0x00483068) and compose its
  per-template text (UpdateProfession @0x004821b0's CustomText/
  BowText/SwashText/LifeText/WarText/WayText/SoldierText, plain
  SetStringInfo — no palette).

- GF-4: UiButton gains a coexisting ValueLabel/ValueBox/ValueFont/
  ValueColor slot alongside Label. Retail's chargen display buttons
  (avail/health/stamina/mana credits, 0x100003e2-e5/0x100003f9)
  author their caption directly on P0x17 AND carry a separate,
  media-less Type-12 value child that UiButton.ConsumesDatChildren
  used to drop entirely — pages substituted the button's own Label,
  destroying the caption. DatWidgetFactory.BuildButton now surfaces
  that child (gated on ReferenceEquals(labelInfo, info) — own-caption
  buttons only) instead. The six Profession slider name labels
  (0x100002ed, CharGenState::GetAttributeName @0x005C3A20's six
  hardcoded literals) resolve as UiButton in this port (live-DAT-
  measured Type 1 — retail's UIElement_Button is DynamicCast(0xc)-
  compatible with UIElement_Text) and are written once at
  construction, matching retail's own single InitializePage write.

- GF-6/AP-218: gmCGAppearancePage::Update writes a heritage-flavored
  STATIC caption to the Hair/Eyes/Skin spins (plain / GearText_* /
  OlthoiText_* variants) — never an index. Removed the prior 1-based-
  ordinal/gear-name substitution entirely; the other six spins keep
  their DAT-authored caption untouched, matching retail exactly.

- Root 1d: wire the Heritage (0x100003be, 13 states) and Profession
  (0x100003d8, 7 states) backdrop SetState cascades
  (gmCGHeritagePage::Update / gmCGProfessionPage::UpdateProfession).

- AP-216/AP-217 (partial, register updated honestly): swatches beyond
  the current part's real color count now hide (DoColorSpots' blank-
  blit half); the GradCircle now blanks for Eyes (DoGradDisk's blank-
  plug half). The "paint with the actual represented/current color"
  halves stay open — they need a PalSet/Palette-id -> RGB pipeline no
  chargen page reads at runtime yet, judged disproportionate to add
  alongside this batch's other ~10 fixes.

Register: AP-215 rewritten (item 2's "ordinal" framing is stale after
GF-6; restated as the icon-thumbnail gap), AP-216/AP-217 rewritten
(partially closed), AP-218 retired, AD-103 retired (the swallowed-
child Label substitution AD-103 tracked is replaced by ValueLabel's
own-geometry surfacing).

22 new tests (DatRichText unit tests, UiButton/DatWidgetFactory
ValueLabel tests, live-DAT structural pins, controller behavioral
tests) — all green. Full App suite (Release, live-DAT):
5300 passed / 1 pre-existing unrelated flake (PortalProjectionTests
allocation test, passes in isolation) / 3 skipped, up from the
baseline 5282/3.

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

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

@@ -0,0 +1,98 @@
+using System;
+using System.Collections.Generic;
+using System.Numerics;
+
+namespace AcDream.App.UI.Layout;
+
+/// <summary>
+/// Shared multi-segment rich-text composer for the chargen description
+/// boxes (Campaign CC gate round 1 Batch C — GF-2/GF-3/GF-11a, and the
+/// Summary how-to text). Ports retail's
+/// <c>UIElement_Text::SetStringInfoWithFont</c> /
+/// <c>AppendStringInfoWithFont @ 0x00469D70</c> composition model: a text
+/// box is built from an ORDERED list of string segments, each carrying its
+/// OWN font-color palette index
+/// (<c>UIElement_Text::AppendStringInfoWithFont</c>'s
+/// <c>SetFontColorHelper</c> -&gt; <c>InqProperty(0x1B)</c> array lookup —
+/// see <see cref="AcDream.App.UI.UiText.FontColorPalette"/>).
+///
+/// <para>
+/// The description pages used to bypass this entirely: they assigned a raw
+/// <c>LinesProvider</c> lambda returning ONE unwrapped <see cref="AcDream.App.UI.UiText.Line"/>
+/// per composed string, with no escape-normalize and no word-wrap. Two
+/// concrete symptoms this caused: literal two-character <c>"\n"</c>
+/// escapes rendered as backslash-n instead of a real line break (the DAT
+/// stores that literal escape — <c>DatWidgetFactory.BuildText</c>'s own
+/// authored-string path already normalizes it for single-element authored
+/// captions; this helper reproduces the SAME normalize for
+/// runtime-composed multi-segment text), and — for the Town page
+/// specifically — an unwrapped single line meant the town-specific SUFFIX
+/// of the composed string rendered far outside the box's clipped viewport,
+/// so switching towns looked like "the text never changes" even though the
+/// underlying string genuinely did (only its INVISIBLE tail differed).
+/// </para>
+/// </summary>
+internal static class DatRichText
+{
+    /// <summary>One composed segment: text plus the color it should render
+    /// in. A null or empty <see cref="Text"/> is silently skipped (mirrors
+    /// retail's own null-string-info no-op guards throughout this text
+    /// composition family).</summary>
+    public readonly record struct Segment(string? Text, Vector4 Color);
+
+    /// <summary>
+    /// Escape-normalizes and word-wraps every segment (independently, so
+    /// each segment's wrapped lines keep ITS OWN color), then concatenates
+    /// the results in order. No separator is inserted between segments —
+    /// retail's own composition calls concatenate directly
+    /// (<c>AppendStringInfoWithFont</c>/<c>append_n_chars</c> with no
+    /// interposed literal), so any blank-line spacing between sections
+    /// comes from the authored DAT string content itself, not from code
+    /// here.
+    /// </summary>
+    public static IReadOnlyList<UiText.Line> Compose(
+        UiText target,
+        IReadOnlyList<Segment> segments)
+    {
+        ArgumentNullException.ThrowIfNull(target);
+        ArgumentNullException.ThrowIfNull(segments);
+
+        var lines = new List<UiText.Line>();
+        float maximumWidth = MathF.Max(1f, target.Width - 2f * target.Padding);
+        Func<string, float> measure = target.DatFont is { } font
+            ? font.MeasureWidth
+            : static value => value.Length * 8f;
+
+        foreach (Segment segment in segments)
+        {
+            if (string.IsNullOrEmpty(segment.Text))
+                continue;
+
+            // The installed DAT stores the LITERAL two-character escape
+            // "\n" (0x5C 0x6E), not a real line break — same normalize
+            // DatWidgetFactory.BuildText's authored-string path already
+            // applies for single-element authored captions.
+            string normalized = segment.Text
+                .Replace("\\n", "\n")
+                .Replace("\r", string.Empty);
+
+            foreach (string wrapped in UiText.WrapWords(normalized, measure, maximumWidth))
+                lines.Add(new UiText.Line(wrapped, segment.Color));
+        }
+
+        return lines;
+    }
+
+    /// <summary>
+    /// Resolves <paramref name="target"/>'s own authored font-color
+    /// palette (dat property <c>0x1B</c>) entry at <paramref name="index"/>,
+    /// falling back to <paramref name="fallback"/> when the palette is
+    /// absent or too short. Mirrors the same fallback shape
+    /// <c>CharacterStatController.BuildSelectedTitleRuns</c> already uses
+    /// for its own palette-indexed colors.
+    /// </summary>
+    public static Vector4 PaletteColor(UiText target, int index, Vector4 fallback) =>
+        index >= 0 && index < target.FontColorPalette.Count
+            ? target.FontColorPalette[index]
+            : fallback;
+}