fix(client): restore retail interaction parity

Harden keyboard and camera routing, inventory and vendor interactions, chat/emotes, relog portal flow, and paperdoll rendering. Add retail research, connected gate coverage, and release-gate validation.

src/AcDream.App/Rendering/PrivateEntityViewportRenderer.cs

@@ -94,6 +94,11 @@ internal sealed class PrivateEntityViewportRenderer :
     /// feature does not exist for them, not just "unused".</summary>
     private readonly EntitySlot? _backdropSlot;
 
+    // One stable sampled texture-table slot is part of the retained viewport's
+    // presentation contract. Rotating the slot with the Vulkan flight index
+    // made the UI sample a freshly-created/cleared sibling after world reveal.
+    // The frame submission order already protects this target's write -> sample
+    // transition; keep its identity stable until resize or disposal.
     private IGpuRenderTarget? _target;
     private IGpuSampler? _sampler;
     private GpuTextureSlot _slot = GpuTextureSlot.Unassigned;
@@ -170,6 +175,29 @@ internal sealed class PrivateEntityViewportRenderer :
 
     public void SetEntity(WorldEntity? entity) => _mainSlot.Set(entity);
 
+    /// <summary>
+    /// Advances the private entity's mesh and texture-composite readiness
+    /// without allocating or clearing a render target. Paperdoll uses this
+    /// while its tab is hidden so first-open work is already resident.
+    /// </summary>
+    public bool Prepare()
+    {
+        if (!_mainSlot.PrepareForDraw()
+            || !(_backdropSlot?.PrepareForDraw() ?? true))
+        {
+            return false;
+        }
+        WorldEntity? entity = _mainSlot.Entity;
+        if (entity is null || entity.MeshRefs.Count == 0)
+        {
+            return false;
+        }
+        IReadOnlyList<WorldEntity> entities = BuildDrawEntities(
+            _backdropSlot?.Entity,
+            entity);
+        return _dispatcher.PreparePrivateEntityResources(entities);
+    }
+
     /// <summary>
     /// Sets or clears the environment backdrop entity drawn BEHIND the main
     /// entity — GF-7/GF-14's fix, retail's <c>gmCG3DView::m_pbgObject</c>. Only
@@ -219,6 +247,16 @@ internal sealed class PrivateEntityViewportRenderer :
         if (entity is null || entity.MeshRefs.Count == 0 || width <= 0 || height <= 0)
             return 0u;
 
+        IReadOnlyList<WorldEntity> drawEntities = BuildDrawEntities(
+            _backdropSlot?.Entity,
+            entity);
+        if (!_dispatcher.PreparePrivateEntityResources(drawEntities))
+        {
+            return _hasRenderedScene && _slot.IsAssigned
+                ? UiTextureTableHandle.FromSlot(_slot)
+                : 0u;
+        }
+
         EnsureRenderTarget(width, height);
         if (_target is null)
             return 0u;
@@ -254,7 +292,6 @@ internal sealed class PrivateEntityViewportRenderer :
 
         UploadCreatureLight();
 
-        IReadOnlyList<WorldEntity> drawEntities = BuildDrawEntities(_backdropSlot?.Entity, entity);
         var entries =
             new (uint, Vector3, Vector3, IReadOnlyList<WorldEntity>,
                 IReadOnlyDictionary<uint, WorldEntity>?)[]