fix(render): S3 chunk 2 review follow-ups

- delete the ACDREAM_PROBE_CATHEDRAL_SKIP_SEALS discriminator (member, read
  site, launch-options row): its investigation is closed by the retail
  axiom, and the review found it had silently gained a second effect through
  the seal count (a skipped seal also suppressed the next depth clear);
- the interior PView's draw_landscape is now wired explicitly (RenderDeviceD3D::Init
  0x0059efb0), so the two-PView pin asserts wiring, not a default;
- the two backend seam comments name retail's clear gate;
- the counter doc states the Collect/Replay consume/re-arm split and why it
  has no retail analogue.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/AcDream.App/Rendering/RetailPViewPassExecutor.cs

@@ -396,13 +396,6 @@ public RetailPViewPassExecutor(
     {
         if (_portalDepthMask is null)
             return 0;
-        if (!forceFarZ
-            && AcDream.Core.Rendering.RenderingDiagnostics
-                .ProbeCathedralSkipFloatingStairSeals
-            && cellId is 0xF4180107u or 0xF4180112u)
-        {
-            return 0;
-        }
         LoadedCell? cell = frame.Cells.Find(cellId);
         if (cell is null)
             return 0;

src/AcDream.App/Rendering/Walk/RetailFrameWalk.cs

@@ -43,7 +43,9 @@ public interface IRetailFrameWalkContext : IWalkBuildingFrameContext
 /// </summary>
 public sealed class RetailFrameWalk
 {
-    private readonly WalkPView _interiorPView = new();
+    // RenderDeviceD3D::Init @0x0059efb0: indoor_pview = PView(…, 1) — the
+    // interior pview DRAWS the landscape through its surviving exit views.
+    private readonly WalkPView _interiorPView = new() { DrawLandscape = true };
     // The outdoor pview never draws the landscape through its look-in
     // floods (the landscape is already drawn when buildings punch), so its
     // draw_landscape is FALSE and look-in DCs always read ov=0 — exactly

src/AcDream.App/Rendering/Walk/WalkFrameDriver.cs

@@ -565,7 +565,11 @@ internal sealed class WalkFrameDriver : IWalkEventSink, IWalkLookInViewSource
     /// frame's read will see. A driver whose interior floods never reach an
     /// exit portal keeps this at zero forever — the gated clear never fires
     /// for it, matching retail exactly (no seals submitted, no depth ever
-    /// needed clearing).</summary>
+    /// needed clearing). Retail consumes and re-arms inside ONE synchronous
+    /// <c>DrawCells</c>; here the consume is at Collect and the re-arm at
+    /// Replay, so a frame that Collects but never Replays (an exception path
+    /// that already failed the frame) leaves the next ov&gt;0 frame without a
+    /// clear — no retail analogue, no production path.</summary>
     internal int PortalsDrawnCount;
 
     IReadOnlyList<uint> IWalkLookInViewSource.LookInCellTurns => LookInCellTurns;

src/AcDream.App/Rendering/WorldPassScope.cs

@@ -96,7 +96,9 @@ internal interface IWorldPassScope
     /// Retail's interior depth clear, scoped to the live pass.
     ///
     /// <para><c>RetailPViewPassExecutor</c> issues <c>glClear(GL_DEPTH_BUFFER_BIT)</c>
-    /// between the landscape slice and the interior cells. Splitting the pass to
+    /// between the landscape slice and the interior cells, only when the walk
+    /// driver's retail gate fires (<c>outside_view.view_count &gt; 0</c> and a
+    /// nonzero <c>portalsDrawnCount</c> — S3 chunk 2). Splitting the pass to
     /// get a depth load-op is exactly what the resolve forbids, so the backend
     /// records <c>vkCmdClearAttachments</c> instead — reached through here, so the
     /// pinned contract stays frozen and the backend-only verb stays inside the

src/AcDream.App/Rendering/WorldPassSurface.cs

@@ -79,7 +79,10 @@ internal interface IWorldPassSurface
 
     /// <summary>
     /// Retail's interior depth clear, between the landscape slice and the
-    /// interior cells (<c>PView::DrawCells @ 0x005A4840</c>).
+    /// interior cells (<c>PView::DrawCells @ 0x005A4840</c>). Retail gates it
+    /// on <c>outside_view.view_count &gt; 0</c> AND a nonzero persistent
+    /// <c>portalsDrawnCount</c> (S3 chunk 2); the walk driver decides, this
+    /// seam only executes.
     /// </summary>
     void ClearInteriorDepth();
 }

src/AcDream.Core/Rendering/RenderingDiagnostics.cs

@@ -119,16 +119,6 @@ public static class RenderingDiagnostics
     public static bool ProbeCathedralSkipStairBuildingPunch { get; set; } =
         Environment.GetEnvironmentVariable("ACDREAM_PROBE_CATHEDRAL_SKIP_PUNCH") == "1";
 
-    /// <summary>
-    /// Temporary cathedral discriminator: suppresses only the true-depth exit
-    /// seals authored by the two cells that meet at the floating-stair seam.
-    /// Both portal polygons lie on world Y ~= 24 and span the reported moving
-    /// triangle. This is a binary visual experiment only; normal production
-    /// behavior is unchanged while the flag is unset.
-    /// </summary>
-    public static bool ProbeCathedralSkipFloatingStairSeals { get; set; } =
-        Environment.GetEnvironmentVariable("ACDREAM_PROBE_CATHEDRAL_SKIP_SEALS") == "1";
-
     /// <summary>
     /// Temporary cathedral carrier discriminator: suppresses only the visible
     /// EnvCell shells for cells 0xF4180107 and 0xF4180112. This deliberately