perf(generation): exact worm block skip with a proven 3D Perlin bound -- measured NEUTRAL

The sampler put the worm carve's first noise call (VoxelGenerator.cpp:3985, FusedWorm) at 19.4% of
LOD0. The worm only carves where N1 + N2 < T with N2 >= 0, so where N1 >= T it contributes nothing,
bit for bit. A block proven to have N1 >= T everywhere can skip both noise calls exactly.

- The Lipschitz bound for this Perlin3D implementation: L = (15/4) * sqrt(3) * 1.25 = 8.118988160,
  in scaled-N1 units, with a 1e-3 float-rounding margin. Adversarial sampling found a worst ratio
  of 3.187 (0.39 L). The existing 2D floor-relief bound (8.5) is a component bound of a different
  field and was confirmed not to transfer.
- A soundness test that can fail (VoxelForgeWormBlockSkipTest): 6,476 proved blocks, 355,945 exact
  lattice samples, 0 violations. A deliberately halved L proves a bad block; the full L rejects it.
- voxel.WormBlockSkip, default 1.

Field exact: export OBJ byte-identical (b3e5f4c3..9b377), 841/841 keyed tiles identical to
NextHeadStaticTrace_20260913, capability 20,830 / 10,909.

RESULT, stated plainly: no measurable speed gain. The skip rate is 4.07% of worm-eligible LOD0
samples and 0% at LOD1-4, because the bound is ~2.5x looser than the worst observed ratio at the
block size used. Paired on-vs-off, two interleaved runs each: static worker +2.15%, generation p50
+1.8%; moving worker -1.42%, request p50 -2.5%. Within noise. The next round turns the default OFF.
The proven bound and its test are kept for a tighter skip later (smaller or hierarchical blocks,
or a per-cell bound).

Run ledger (from Codex's report): the first build failed on an ambiguous test overload and was
fixed; two timing runs are void because the orchestrator stopped the session so the owner could
use the PC; the eight valid timing runs, the sampler run and the diagnostics runs completed. No
new crash folders. PERF-SAMPLED.md now lists all eight earlier-round UECC crash records.

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

Source/VoxelForge/Private/VoxelWorld.cpp

@@ -3860,6 +3860,16 @@ void AVoxelWorld::GenerateTileResult(const FVoxelTileKey& Tile, const FIntVector
                 CycleDelta(VoxelDensityProfile::EBucket::RoomGraphBuild));
             const double EvaluationSeconds = FMath::Max(
                 0.0, TileSeconds - CacheBuildSeconds);
+            const uint64 WormEligibleSamples = CounterDelta(
+                VoxelDensityProfile::ECounter::WormEligibleSamples);
+            const uint64 WormBlockProofs = CounterDelta(
+                VoxelDensityProfile::ECounter::WormBlockProofs);
+            const uint64 WormBlockSkippedSamples = CounterDelta(
+                VoxelDensityProfile::ECounter::WormBlockSkippedSamples);
+            const double WormBlockSkipRate = WormEligibleSamples > 0
+                ? static_cast<double>(WormBlockSkippedSamples)
+                    / static_cast<double>(WormEligibleSamples)
+                : 0.0;
             UE_LOG(LogTemp, Display,
                 TEXT("[VoxelForgeTileProfile] tile=(%d,%d,%d) level=%d step=%d cells=%d sheet=%d aborted=%d empty=%d "
                      "verdict=%d classify=%.6f mesh=%.6f streams=%.6f seconds=%.6f "
@@ -3876,7 +3886,9 @@ void AVoxelWorld::GenerateTileResult(const FVoxelTileKey& Tile, const FIntVector
                      "cache_op_local=%llu cache_classifier_shared=%llu cache_classifier_local=%llu "
                      "cache_unknown=%llu room_candidates=%llu room_evaluated=%llu "
                      "tunnel_candidates=%llu tunnel_evaluated=%llu tunnel_core_candidates=%llu "
-                     "tunnel_core_evaluated=%llu support_column_candidates=%llu"),
+                     "tunnel_core_evaluated=%llu support_column_candidates=%llu "
+                     "worm_eligible=%llu worm_block_proofs=%llu worm_block_skipped=%llu "
+                     "worm_skip_rate=%.6f"),
                 Tile.Coord.X, Tile.Coord.Y, Tile.Coord.Z, Tile.Level, Step, Cells,
                 bSheetTile ? 1 : 0, Result.bAborted ? 1 : 0,
                 Result.bEmpty ? 1 : 0, ClassifyVerdict, ClassifySeconds, MeshSeconds, StreamSeconds,
@@ -3918,7 +3930,11 @@ void AVoxelWorld::GenerateTileResult(const FVoxelTileKey& Tile, const FIntVector
                 static_cast<unsigned long long>(CounterDelta(VoxelDensityProfile::ECounter::CaveTunnelEvaluated)),
                 static_cast<unsigned long long>(CounterDelta(VoxelDensityProfile::ECounter::TunnelCoreCandidates)),
                 static_cast<unsigned long long>(CounterDelta(VoxelDensityProfile::ECounter::TunnelCoreEvaluated)),
-                static_cast<unsigned long long>(CounterDelta(VoxelDensityProfile::ECounter::TunnelSupportColumnCandidates)));
+                static_cast<unsigned long long>(CounterDelta(VoxelDensityProfile::ECounter::TunnelSupportColumnCandidates)),
+                static_cast<unsigned long long>(WormEligibleSamples),
+                static_cast<unsigned long long>(WormBlockProofs),
+                static_cast<unsigned long long>(WormBlockSkippedSamples),
+                WormBlockSkipRate);
 
             if (bProfileOps)
             {