wip(assembler): round S7 -- workers kept busy: in-game cold full view 17.5 s -> 7.8 s

Two admission blockers found by per-frame decline codes: the near reserve held
four slots idle after LOD0 was done (coarse capped at 6), and finished-but-
unapplied results counted against the task cap. Admission now counts queued +
running tasks; near reserve releases once the walkable ring is ready while
stationary (voxel.StreamingDynamicNearReserve, default on). Walkable ring
0.65 -> 0.58 s, full LOD0 2.28 -> 1.44 s, busy workers 2.2 -> 5.6 of 10.
Old behaviour behind voxel.StreamingLegacyPendingResultCap. RMC source reviewed
(read-only): batching/fast-cook ranked, not yet worth it on measured apply cost.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MmSoF64BbRFmk9C3p1VsBJ

Tools/TestVoxelForgeCoreWorldHost.ps1

@@ -3,6 +3,7 @@ param(
     [ValidateRange(60, 900)][int]$TimeoutSeconds = 900,
     [ValidateRange(12.5, 25.0)][double]$CoreVoxelSizeCm = 25.0,
     [ValidateSet('CoarseFirst', 'Legacy')][string]$StreamingOrder = 'Legacy',
+    [ValidateSet('Auto', 'Legacy', 'Dynamic')][string]$NearReserveMode = 'Auto',
     [switch]$EnforceCollisionGate,
     [switch]$StartupTrace,
     [ValidateRange(0, 1)][int]$StartupApplyBoost = 0,
@@ -145,6 +146,11 @@ if ($SharedFeatureAuditOnly) {
     $RunName = 'shared_feature_audit'
 }
 $RunName += if ($StreamingOrder -eq 'Legacy') { '_legacy_order' } else { '_coarse_first' }
+$RunName += switch ($NearReserveMode) {
+    'Legacy' { '_nearreserve_legacy' }
+    'Dynamic' { '_nearreserve_dynamic' }
+    default { '_nearreserve_auto' }
+}
 if ($EnforceCollisionGate) { $RunName += '_collision_gate' }
 if ($StartupTrace -or $StreamingTraceOnly) { $RunName += '_trace' }
 
@@ -262,9 +268,15 @@ $BaseArguments = @(
     ('-out="{0}"' -f $OutputDirectory)
 )
 $CoarseFirstValue = if ($StreamingOrder -eq 'CoarseFirst') { 1 } else { 0 }
-$DynamicReserveValue = if ($StreamingOrder -eq 'CoarseFirst') { 1 } else { 0 }
+$DynamicReserveValue = switch ($NearReserveMode) {
+    'Legacy' { 0 }
+    'Dynamic' { 1 }
+    default { 1 }
+}
+$LegacyPendingResultCapValue = if ($NearReserveMode -eq 'Legacy') { 1 } else { 0 }
 $BaseArguments += "-voxel.StreamingCoarseFirst=$CoarseFirstValue"
 $BaseArguments += "-voxel.StreamingDynamicNearReserve=$DynamicReserveValue"
+$BaseArguments += "-voxel.StreamingLegacyPendingResultCap=$LegacyPendingResultCapValue"
 $BaseArguments += "-voxel.StreamingStartupApplyBoost=$StartupApplyBoost"
 if ($StreamingTraceOnly) {
     $BaseArguments += '-coreworldstreamtrace=1'