fix: enforce Local G2 total window length

ClumsyPilot/tests/verify_path_smoothing_local_g2_detection.ps1

@@ -93,4 +93,37 @@ Assert-True (-not [string]::IsNullOrWhiteSpace([string]$overflowArguments[4])) `
     'Rejected overflow detection must provide a stable reason.'
 Assert-Equal 0 $overflowArguments[3].Count 'Rejected overflow detection must not publish a curvature event.'
 
+$plannerType = Get-RequiredType 'MultiWheelC.TrajectoryPlanning.PathSmoothing.LocalG2.LocalG2WindowPlanner'
+$plannerHooksType = $plannerType.GetNestedType('TestHooks', [Reflection.BindingFlags]'Public,NonPublic')
+Assert-True ($null -ne $plannerHooksType) 'LocalG2WindowPlanner must expose narrow deterministic TestHooks.'
+$planScenario = $plannerHooksType.GetMethod('Execute', [Reflection.BindingFlags]'Public,Static')
+
+$separated = $planScenario.Invoke($null, @('SeparatedByOneMeter'))
+Assert-Equal 2 $separated.RegionCount 'Events 1.0 m apart cannot share a 0.80 m total window.'
+Assert-Equal '1,1' $separated.TransitionCounts 'Separated events must remain one event per region.'
+
+$mergeable = $planScenario.Invoke($null, @('Mergeable'))
+Assert-Equal 1 $mergeable.RegionCount 'Events covered by one legal total window must merge.'
+Assert-Equal '2' $mergeable.TransitionCounts 'The merged region must retain both events.'
+
+$partition = $planScenario.Invoke($null, @('ThreeEventPartition'))
+Assert-Equal 2 $partition.RegionCount 'Three events must split at the first infeasible joint window.'
+Assert-Equal '2,1' $partition.TransitionCounts 'Only a feasible consecutive subgroup may merge.'
+
+$boundary = $planScenario.Invoke($null, @('NearBoundary'))
+Assert-True ($boundary.FirstRightLength -gt $boundary.FirstLeftLength) `
+    'A boundary-clamped total window must transfer missing length to the available side.'
+Assert-True ($boundary.MaximumWindowLength -le 0.80 + 1e-9) `
+    'No candidate window may exceed 0.80 m total length.'
+
+foreach ($snapshot in @($separated, $mergeable, $partition, $boundary)) {
+    Assert-True $snapshot.ExactEnvelope 'Region envelope must equal the extrema of actual legal variants.'
+    Assert-True ($snapshot.MaximumWindowLength -le 0.80 + 1e-9) `
+        'MaximumWindowLengthMeters is a total, not a per-side length.'
+}
+
+$repeat = $planScenario.Invoke($null, @('ThreeEventPartition'))
+Assert-Equal $partition.Signature $repeat.Signature `
+    'Repeated planning must preserve grouping, candidate numbering and variant order.'
+
 Write-Output 'Path smoothing Local G2 detection checks passed.'