Initial shared Copilot resources scaffold

install/update.ps1

@@ -0,0 +1,12 @@
+$ErrorActionPreference = 'Stop'
+
+$ScriptDir = Split-Path -Parent $MyInvocation.MyCommand.Path
+$RepoRoot = Split-Path -Parent $ScriptDir
+
+if (Test-Path -LiteralPath (Join-Path $RepoRoot '.git')) {
+    git -C $RepoRoot pull --ff-only
+} else {
+    Write-Host 'Skipping git pull because this repository is not initialized as a git repository yet.'
+}
+
+& (Join-Path $ScriptDir 'verify.ps1') -Quick