feat(ui): Campaign OP slice OP5 — the Chat tab

Binds LayoutDesc 0x2100005C through OP2's template-list mechanism and
OP3's per-page OptionPage model: the General Options header + two
DualHash-linked opacity sliders (Option_DefaultOpacity_Property
0x10000080 / Option_ActiveOpacity_Property 0x10000081, live-apply on
drag through RetailWindowOpacityController, defaults read from the
installed DAT's DBProperties collection at DID 0x78000001 via
ChatOptionsDatDefaults), and the five per-window text-filter blocks
(main window 12 rows minus Gameplay, four floaties 13 rows each — the
byte-verified authored order cross-checked against the raw
gmChatOptionsUI::InitOptions/AddCheckboxBitfield64Option pseudo-C, not
just the research doc's own table) writing AcDream.Core.Chat.
ChatWindowState directly, the same state CH6's chat windows already
read.

AP-195 retired: ported both halves left open at the OP2 re-review —
the ALL-set LED media swap (new UiButton.FaceFileOverride, driven by
the block-level P0x10000082/P0x10000083 sprites now threaded through
ElementInfo/DatWidgetFactory) and the CreateChildren self-sizing tail
(UiCheckboxBitfield64.Height grows with its stacked row content; the
enclosing ListBox reflows around the block's FINAL height via the new
UiTemplateListBox.AddPrebuiltRow, reusing the ListBox's own stacking
rather than a third stacking path). AP-187 broadened to cover the main
window's own filter (previously only the four floaties) and the new
live-editing write path.

The main chat window's filter (retail window id 8, ChatWindowState id
0) gains its own settings.json persistence (ChatSettings.
ChatWindowMainFilter) alongside the pre-existing floaty 1-4 fields;
opacity persistence is now wired on every live slider change, not only
through the old dev-scaffold Settings panel.

Fixture regeneration (ACDREAM_REGENERATE_UI_FIXTURES=1) picked up the
new ElementInfo.LedCheckedSprite/LedUncheckedSprite fields across all
19 committed layout fixtures — purely additive, confirmed against the
live installed DAT (0x10000520's own 0x82/0x83 properties resolve to
0x06004D17/0x06004D19 exactly as AP-195 documented).

Conformance: FilterRows/FilterBlocks pinned against the byte-verified
authored order and ChatWindowState's own default constants; the AP-195
LED swap and self-sizing behavior; the DAT opacity-default extraction
against the live installed DAT; live filter/opacity writes reaching
ChatWindowState/RetailWindowOpacityController; OnShown re-seed and
Reset/Defaults ghosting per the OP4 binding-pattern discipline.

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

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

@@ -0,0 +1,92 @@
+using AcDream.Content;
+using DatReaderWriter.DBObjs;
+using DatReaderWriter.Types;
+
+namespace AcDream.App.UI.Layout;
+
+/// <summary>
+/// Campaign OP slice OP5: reads the Chat tab's two opacity-slider defaults from the
+/// installed DAT's <c>DBProperties</c> collection — retail
+/// <c>UIOption::InqDefaultGameplayOptionProperty @0x004ef8d0</c>'s
+/// <c>m_propName</c>-bound path, the ONE genuine consumer of that mechanism (the
+/// Character tab's 49/50 checkboxes are <c>PlayerOption</c>-bound, not
+/// <c>m_propName</c>-bound — see <see cref="CharacterOptionsPageController"/>'s own
+/// U1 trace for why THAT tab does not use this seam).
+///
+/// <para>
+/// Byte-verified recipe (<c>DBCache::GetDIDFromEnum @0x00413940</c>): the outer call
+/// site is <c>GetDIDFromEnumStatic(&amp;ret, 0x16, 2)</c> — outer arg2 (<c>0x16</c>)
+/// feeds the inner function's arg3 (the SUB-MAP lookup key), outer arg3 (<c>2</c>)
+/// feeds arg4 (the MASTER-MAP lookup key FIRST). So:
+/// <c>master.ClientEnumToID[2] → subMapDid; subMap.ClientEnumToID[0x16] → DID</c> —
+/// i.e. <see cref="RetailDataIdResolver.Resolve"/>'s own <c>(enumValue, enumCategory)</c>
+/// parameter order is <c>(0x16, 2)</c>, matching
+/// <c>RetailUiRuntime.cs</c>'s existing <c>Resolve(dats, 2u, 5u)</c> convention
+/// (enumCategory selects the master-map submap FIRST, enumValue indexes it SECOND).
+/// Empirically confirmed against the installed DATs: resolves to DID
+/// <c>0x78000001</c>, a 3-entry <c>DBProperties</c> —
+/// <c>0x1000007F</c> (<c>Bitfield64</c>, the Chat filter blocks' shared
+/// <c>m_propName</c> — NOT a per-window default; the five blocks' actual defaults are
+/// the literal constants <c>gmChatOptionsUI::InitOptions</c> authors per window,
+/// ported verbatim in <c>ChatWindowState</c>/<see cref="ChatOptionsPageController"/>),
+/// <c>0x10000080</c> (<c>Float</c>, <c>0.5</c> — <c>Option_DefaultOpacity_Property</c>),
+/// <c>0x10000081</c> (<c>Float</c>, <c>1.0</c> — <c>Option_ActiveOpacity_Property</c>).
+/// </para>
+/// </summary>
+public static class ChatOptionsDatDefaults
+{
+    /// <summary>DAT enum-category key for the FIRST (master-map) lookup — see the
+    /// class doc's byte-verified recipe.</summary>
+    private const uint EnumCategory = 2u;
+
+    /// <summary>DAT enum-value key for the SECOND (sub-map) lookup.</summary>
+    private const uint EnumValue = 0x16u;
+
+    /// <summary><c>Option_DefaultOpacity_Property</c> — the unfocused-window opacity
+    /// slider's <c>m_propName</c>.</summary>
+    public const uint DefaultOpacityPropertyId = 0x10000080u;
+
+    /// <summary><c>Option_ActiveOpacity_Property</c> — the focused-window opacity
+    /// slider's <c>m_propName</c>.</summary>
+    public const uint ActiveOpacityPropertyId = 0x10000081u;
+
+    /// <summary>Retail base-constructor fallback (<c>ChatInterface::ChatInterface
+    /// @0x004F4550</c>) — used only when the DAT read fails (missing DAT entry,
+    /// corrupt install); the live installed DAT resolves to these exact values today.</summary>
+    public const float FallbackDefaultOpacity = 0.5f;
+
+    public const float FallbackActiveOpacity = 1.0f;
+
+    /// <summary>
+    /// Resolves the two slider defaults from the live DAT. Returns
+    /// <see langword="false"/> (with both out params set to the retail-constructor
+    /// fallback) if the DID does not resolve, the <c>DBProperties</c> object is
+    /// missing, or either property is absent/not a <c>Float</c> — matching this
+    /// codebase's "degrade to a documented fallback, never invent a value" discipline.
+    /// </summary>
+    public static bool TryRead(
+        IDatReaderWriter dats, out float defaultOpacity, out float activeOpacity)
+    {
+        defaultOpacity = FallbackDefaultOpacity;
+        activeOpacity = FallbackActiveOpacity;
+
+        uint did = RetailDataIdResolver.Resolve(dats, EnumValue, EnumCategory);
+        if (did == 0u || !dats.Portal.TryGet<DBProperties>(did, out DBProperties? props) || props is null)
+            return false;
+
+        bool ok = true;
+        if (props.Properties.TryGetValue(DefaultOpacityPropertyId, out BaseProperty? d)
+            && d is FloatBaseProperty defaultProp)
+            defaultOpacity = defaultProp.Value;
+        else
+            ok = false;
+
+        if (props.Properties.TryGetValue(ActiveOpacityPropertyId, out BaseProperty? a)
+            && a is FloatBaseProperty activeProp)
+            activeOpacity = activeProp.Value;
+        else
+            ok = false;
+
+        return ok;
+    }
+}