fix(streaming): the player can walk from one strate into the next

Owner playtest: he could not walk from strate A into B. Forcing the pawn through in the editor
showed the junction tunnel (and his edits to the lower strate) were there.

Cause: UVoxelSettings::StrateContentCutMinLevel defaulted to 0, and DA_Settings does not override
it, so the strate content band (the PAWN's strate) also cut LOD0, the collision tiles. While the
player stood in A, the passage below A's seal, the gap and strate B had no LOD0 geometry, and the
collision gate correctly refused to step onto missing collision. The band only moves once the pawn
is inside B: a deadlock. bClampViewToStrate is a different setting, which is why toggling it did
not help. Some historical fall-throughs were likely this, before the gate turned "fall" into
"blocked".

Fix (Codex; reviewed by me):
- StrateContentCutMinLevel default 0 -> 1, ClampMin 1, and
  UVoxelSettings::GetEffectiveStrateContentCutMinLevel() clamps to [1,9] at every runtime
  consumer, so a legacy asset serialising 0 cannot bring the deadlock back. LOD1+ stay banded
  inside strates and go full in the gap.
- A regression test, -voxel.TestStrateCrossing=1 (off unless passed): it walks the real manager
  passage control points with AddMovementInput and normal swept character movement, with limits
  of 10 s max gate, 120 s total and a 2-voxel floor tolerance. Old code: FAIL
  collision_gate_timeout at route 5/9 (10.0 s gated). Fixed: PASS reached_lower_strate, strate
  0 -> 1, max gate 0.092 s. The trace shows band [-7..0] -> full in the gap -> [-17..-10].

Field unchanged: canonical export b3e5f4c3..9b377, capability 20,830 / 10,909. In game, the LOD0
change in the crossing scene is 11 transition-gap tiles going from 0 to 22,390 triangles; no LOD0
interior tile changed.

COST, stated plainly (two interleaved runs, baseline vs fixed DLL):
  static  generation CPU 34.1 -> 44.1 s (+29%), density calls +23%, LOD0 request p95 +8.9%
  moving  generation CPU 78.8 -> 91.1 s (+16%), density calls +26%, LOD0 request p95 +3.1%
  applied triangles identical (669,834 / 1,331,482): the extra work is LOD0 tiles in sealed rock
  that the old cut skipped. The next round proves them solid instead of sampling them.

Visual caveat: the old default of 0 was a deliberate July choice, because LOD0/1 tiles straddling
a strate boundary mixed both strates' materials. With LOD0 never cut, that mixing may reappear
near seals. The headless runs are -nullrhi, so this still needs checking in the editor.

Launches: all serialized and waited by PID. Failures: one malformed first baseline attempt, one
over-strict early harness assertion, and one run against stale staging (it logged CutMinLevel=0),
all superseded.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TaFdXhTdYMkW1xrV6ApT6Y

Source/VoxelForgeEditor/Private/VoxelForgeExploreCommandlet.cpp

@@ -5780,7 +5780,7 @@ int32 RunExploreCase(const FString& Params, FString* OutJson)
             ? FMath::Clamp(World.Settings->CoarseTileCells, 4, CHUNK_SIZE)
             : 16;
         const int32 CutMin = World.Settings
-            ? World.Settings->StrateContentCutMinLevel
+            ? World.Settings->GetEffectiveStrateContentCutMinLevel()
             : 9;
         for (int32 Level = 0; Level <= 4; ++Level)
         {