Review changes batch 6 of 6

tests/capture-g03-states-contract.ps1

@@ -0,0 +1,23 @@
+$ErrorActionPreference = 'Stop'
+
+$root = Split-Path -Parent $PSScriptRoot
+$capture = Get-Content -LiteralPath (Join-Path $root 'scripts/capture-chrome-page.js') -Raw -Encoding utf8
+
+foreach ($required in @(
+  'prepareG03State',
+  'g03-create-validation',
+  'g03-duplicate-reminder',
+  'g03-create-submitting',
+  'g03-create-error',
+  'g03-ancestor-validation',
+  'g03-ancestor-submitting',
+  'g03-ancestor-error',
+  'g03-ancestor-success'
+)) {
+  if ($capture -notmatch [regex]::Escape($required)) { throw "G03 capture state missing: $required" }
+}
+
+if ($capture -notmatch 'await prepareG03State\(send, action\)') { throw 'Capture runner does not prepare G03 states' }
+if ($capture -notmatch 'action\?\.endsWith\(''-submitting''\)') { throw 'Capture runner does not shorten settle time for transient submitting states' }
+
+Write-Output 'CAPTURE-G03-STATES-CONTRACT PASS'