ensure deps downloaded

Author: ramsessanchez

.azure-pipelines/common-templates/install-tools.yml

@@ -75,6 +75,22 @@ steps:
       workingDir: $(Build.SourcesDirectory)
       customCommand: install -g @autorest/core@3.10.4 --registry https://microsoftgraph.pkgs.visualstudio.com/0985d294-5762-4bc2-a565-161ef349ca3e/_packaging/PowerShell_V2_Build/npm/registry/
 
+  - task: PowerShell@2
+    displayName: Pre-populate autorest core cache
+    inputs:
+      targetType: inline
+      pwsh: true
+      script: |
+        # Autorest looks for @autorest/core in ~/.autorest/@autorest/core/<version>/node_modules/
+        # Pre-installing it here with the explicit registry flag means autorest never needs
+        # to make any npm calls during module generation.
+        $cacheDir = Join-Path $env:USERPROFILE ".autorest\@autorest\core\3.10.4"
+        New-Item -ItemType Directory -Force -Path $cacheDir | Out-Null
+        Write-Host "Pre-installing @autorest/core@3.10.4 into autorest cache: $cacheDir"
+        npm install @autorest/core@3.10.4 --prefix $cacheDir --registry https://microsoftgraph.pkgs.visualstudio.com/0985d294-5762-4bc2-a565-161ef349ca3e/_packaging/PowerShell_V2_Build/npm/registry/
+        if ($LASTEXITCODE -ne 0) { throw "Failed to pre-install @autorest/core@3.10.4 into autorest cache (exit $LASTEXITCODE)" }
+        Write-Host "Autorest core cache pre-populated successfully"
+
   - task: Npm@1
     displayName: Install Rush
     inputs: