feat(phys L.2a slice 2): include hit object guid in [resolve] probe

Extends the existing [resolve] probe line to surface
ci.LastCollidedObjectGuid (hit object) + ci.CollidedWithEnvironment
(terrain hit flag) + ci.CollideObjectGuids.Count (when >1) so the
operator can tell WHICH entity the wall is, not just the wall normal.

Tonight's L.2a slice 1 trace caught a clean wall-slide at the
Holtburg-area doorway (n=(0,1,0), 122 hit=yes lines), but had no way
to attribute the hit to a specific entity — the L.2d sub-direction
call (door collision shape vs building wall mesh) needs the entity id
to pick the right fix. This extension provides it on the next run.

Format change for [resolve] hit field:
  Before: hit=yes n=(0.00,1.00,0.00)
  After:  hit=yes n=(0.00,1.00,0.00) obj=0xCC0CXXXX
          hit=yes n=(0.00,1.00,0.00) env
          hit=yes n=(0.00,1.00,0.00) obj=0xCC0CXXXX env nObj=3

Pure additive within the existing PhysicsDiagnostics.ProbeResolveEnabled
gate. No new env var, no new file. Build green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/AcDream.Core/Physics/PhysicsEngine.cs

@@ -691,10 +691,30 @@ public sealed class PhysicsEngine
             string probeCp = ci.ContactPlaneValid
                 ? "valid"
                 : (ci.LastKnownContactPlaneValid ? "lastKnown" : "none");
-            string probeHit = collisionNormalValid
+            string probeHit;
-                ? System.FormattableString.Invariant(
+            if (collisionNormalValid)
-                    $"yes n=({collisionNormal.X:F2},{collisionNormal.Y:F2},{collisionNormal.Z:F2})")
+            {
-                : "no";
+                // L.2a slice 2 (2026-05-12): include the hit object's guid +
+                // environment flag so we can tell whether the wall is a building
+                // (CBuildingObj), a door (CC0Cxxxx range), an NPC, or terrain.
+                // Without this we know the wall normal but not the responsible
+                // entity — half the L.2d sub-direction call.
+                string objPart = ci.LastCollidedObjectGuid.HasValue
+                    ? System.FormattableString.Invariant(
+                        $" obj=0x{ci.LastCollidedObjectGuid.Value:X8}")
+                    : "";
+                string envPart = ci.CollidedWithEnvironment ? " env" : "";
+                int objCount = ci.CollideObjectGuids.Count;
+                string objCountPart = objCount > 1
+                    ? System.FormattableString.Invariant($" nObj={objCount}")
+                    : "";
+                probeHit = System.FormattableString.Invariant(
+                    $"yes n=({collisionNormal.X:F2},{collisionNormal.Y:F2},{collisionNormal.Z:F2}){objPart}{envPart}{objCountPart}");
+            }
+            else
+            {
+                probeHit = "no";
+            }
             Console.WriteLine(System.FormattableString.Invariant(
                 $"[resolve] ent=0x{movingEntityId:X8} in=({currentPos.X:F3},{currentPos.Y:F3},{currentPos.Z:F3}) cell=0x{cellId:X8} tgt=({targetPos.X:F3},{targetPos.Y:F3},{targetPos.Z:F3}) out=({probePost.X:F3},{probePost.Y:F3},{probePost.Z:F3}) cell=0x{sp.CheckCellId:X8} ok={ok} groundedIn={isOnGround} cp={probeCp} hit={probeHit} walkable={sp.HasLastWalkablePolygon}"));
         }