tools(i422): parameterised debug-heap loop + plain rate loop; #422 re-characterised after it fired on the retail matrix row

The fault is pack-independent (fired on the retail preset, 1080p, 45 s,
first launch after a build), ~1 in 57 offline runs today, never under a
debugger (46 runs), no WER/event trace on this machine. The pre-campaign
binary cannot be measured with this gate (no in-process close verb).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tools/i422/loop-debugheap.ps1

@@ -5,11 +5,18 @@
     summarised to artifacts/i422dh/summary.txt.
 .EXAMPLE
     pwsh tools/i422/loop-debugheap.ps1 -Runs 24
+    # the recipe that reproduced #422 at VM7 (retail preset, 1080p, 45 s warm-up):
+    pwsh tools/i422/loop-debugheap.ps1 -Runs 8 -Preset retail -Resolution 1920x1080 -WarmupMs 45000 -OutLeaf i422dh-retail1080
 #>
-param([int]$Runs = 24)
+param(
+    [int]$Runs = 24,
+    [ValidateSet('retail', 'low', 'medium', 'high', 'auto')][string]$Preset = 'high',
+    [string]$Resolution = '1280x720',
+    [int]$WarmupMs = 12000,
+    [string]$OutLeaf = 'i422dh')
 $ErrorActionPreference = 'Continue'
 $repo = (Resolve-Path (Join-Path $PSScriptRoot '..\..')).Path
-$root = Join-Path $repo 'artifacts\i422dh'
+$root = Join-Path $repo ('artifacts' + [IO.Path]::DirectorySeparatorChar + $OutLeaf)
 New-Item -ItemType Directory -Force $root | Out-Null
 $summary = Join-Path $root 'summary.txt'
 "run,gateExit,shutdownLine,heapLine" | Set-Content $summary
@@ -19,7 +26,7 @@ for ($i = 1; $i -le $Runs; $i++) {
     $gateErr = Join-Path $root ("gate-{0:D2}.err" -f $i)
     $gate = Start-Process -FilePath 'pwsh' -ArgumentList @(
         '-NoProfile', '-File', (Join-Path $repo 'tools\run-offline-pixel-gate.ps1'),
-        '-Out', $out, '-SkipBuild', '-RenderPackPreset', 'high', '-Uncapped',
+        '-Out', $out, '-SkipBuild', '-RenderPackPreset', $Preset, '-Resolution', $Resolution, '-WarmupMs', "$WarmupMs", '-Uncapped',
         '-DebuggerScript', (Join-Path $repo 'tools\cdb\i422-heap-launch.cdb')) `
         -PassThru -WindowStyle Hidden -RedirectStandardOutput $gateOut -RedirectStandardError $gateErr
     $gate.WaitForExit()