fix #389: port retail's SmartboxFOV law; retire AD-89 (display slice 1)

Retail's world-camera FOV is not a constant: the applied vertical FOV is
m_fGameFOV / (viewportAspect - 0.1), recomputed on every aspect or
game-FOV change (CreatureMode smartbox sites 0x00452b2f/0x00453b14),
gated by Render::SetFOVRad's open (0, pi) acceptance (0x0054b2d0 -
rejected results keep the previous FOV). m_fGameFOV defaults to pi/2 =
90 degrees (0x00454649) and is what the Field of View option sets in
degrees (0x00451e6a; registered range [10,160] default 90 -
gmClient::InitUIPreferences @0x004035b0). Net effect: the horizontal
view stays ~85-90 degrees across aspect ratios; wide screens trim the
vertical slice instead of ballooning the sides.

acdream hardcoded FovY = pi/3 = 60 degrees on all four world cameras,
aspect-independent, and the Config slider wrote raw vertical-FOV
degrees. New: RetailFieldOfView (the law + gate, decomp-cited),
CameraController.GameFovRadians + SetGameFov + one ApplyProjection
chokepoint recomputing every camera on SetAspect/SetGameFov/
EnterChaseMode/RestoreState; ApplyFieldOfView now feeds the law;
DisplaySettings.Default.FieldOfView 60 -> 90 (the retail registered
default; the stored number changed MEANING with this commit).

The same seam closes a second latent bug the 2026-08-13 "squished" gate
report exposed: SetAspect only ever updated Orbit/Fly - the CHASE
cameras (the ones the player looks through) kept their creation-time
aspect across every mid-session resize, drawing the world at the old
shape stretched onto the new viewport.

The paperdoll camera stays outside the law by design (retail portrait
mode is UseSharpMode, not smartbox - DollCamera's own doc).

Tests: RetailFieldOfViewTests (golden law values at 4:3/16:9/21:9, the
constant-horizontal property, the rejection gate, controller propagation
incl. chase attach/restore + rejected-law aspect-still-propagates);
DisplaySettingsTests + RuntimeSettingsControllerTests updated to the new
semantics. App suite 4,953/3 skips; UI.Abstractions 916/0. AD-89 retired
in this commit; user settings.json migrated 60->90 by hand (stale
pre-port default).

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

src/AcDream.UI.Abstractions/Panels/Settings/DisplaySettings.cs

@@ -79,15 +79,18 @@ public sealed record DisplaySettings(
 {
     /// <summary>Values used on first launch / when settings.json is absent.
     /// Geometry defaults preserve the pre-L.0 runtime state: Resolution
-    /// matches the WindowOptions startup size (1280×720) and FieldOfView
-    /// matches camera FovY (60°). VSync defaults on so normal rendering is
-    /// synchronized to the active monitor, while
+    /// matches the WindowOptions startup size (1280×720). FieldOfView is
+    /// retail's <c>m_fGameFOV</c> in degrees — registered default 90, range
+    /// [10,160] (<c>gmClient::InitUIPreferences @0x004035b0</c>; #389
+    /// corrected the pre-port 60, which encoded the old direct-vertical-FOV
+    /// semantics this record no longer means). VSync defaults on so normal
+    /// rendering is synchronized to the active monitor, while
     /// ShowFps matches retail's initially-hidden SmartBox FPS readout.</summary>
     public static DisplaySettings Default { get; } = new(
         Resolution:   "1280x720",
         Fullscreen:   false,
         VSync:        true,
-        FieldOfView:  60f,
+        FieldOfView:  90f,
         Gamma:        1.0f,
         ShowFps:      false,
         Quality:      QualityPreset.High,