perf(vfx): port retail particle visibility degradation

Resolve DAT-authored particle ranges from the hardware GfxObj, apply retail distance and completed-cell visibility gates, and preserve the exact finite/infinite off-view update semantics. This removes dense-world simulation work without shortening terrain, entity, fog, or streaming distance.

Publish doorway-clipped outdoor cells through a focused frame controller, retain effect cell identity for outdoor statics, reject hidden emitters before particle-slot scans, and offer an explicit opt-in Extended particle range.

Release build succeeds and all 5,857 tests pass with five intentional skips. Retail-conformance, architecture, and adversarial review cycles are clean; connected Aerlinthe visual/performance gate pending.

Co-authored-by: OpenAI Codex <codex@openai.com>

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

@@ -236,12 +236,20 @@ public sealed class SettingsPanel : IPanel
         if (renderer.Combo("Quality", ref qIdx, presets))
             _vm.SetDisplay(d with { Quality = (QualityPreset)qIdx });
 
+        int particleRangeIndex = (int)d.ParticleRange;
+        if (particleRangeIndex < 0 || particleRangeIndex >= s_particleRangeNames.Length)
+            particleRangeIndex = (int)ParticleRange.Retail;
+        if (renderer.Combo("Particle Range", ref particleRangeIndex, s_particleRangeNames))
+            _vm.SetDisplay(d with { ParticleRange = (ParticleRange)particleRangeIndex });
+
         renderer.Spacing();
         renderer.TextWrapped(
             "Resolution / Fullscreen / V-Sync apply on Save. FOV + Gamma "
             + "preview live as you drag; Cancel reverts to the saved value. "
             + "Quality preset applies streaming radius, anisotropic, and A2C "
-            + "immediately on Save; MSAA sample count requires a restart.");
+            + "immediately on Save; MSAA sample count requires a restart. "
+            + "Particle Range defaults to retail-authored distances; Extended "
+            + "doubles effect range and costs additional CPU time.");
     }
 
     /// <summary>
@@ -474,6 +482,9 @@ public sealed class SettingsPanel : IPanel
     private static readonly string[] s_qualityPresetNames =
         { "Low", "Medium", "High", "Ultra" };
 
+    private static readonly string[] s_particleRangeNames =
+        { "Retail", "Extended" };
+
     private void RenderSection(IPanelRenderer renderer, string label, InputAction[] actions)
     {
         // Movement defaults open; other sections collapsed for first-run UX.