Fix web.config patch: use XPath instead of property navigation

Property-path navigation returns an empty string when the <location>
wrapper is absent from the published web.config, causing AppendChild
to fail. SelectSingleNode("//aspNetCore") works regardless of structure.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Jenkinsfile.dev

@@ -68,24 +68,30 @@ pipeline {
                 powershell '''
                     $path = "C:\\inetpub\\wwwroot\\web.config"
                     $xml = [xml](Get-Content $path)
-                    $aspNetCore = $xml.configuration.location.'system.webServer'.aspNetCore
+
+                    # Use XPath so the structure (with or without <location> wrapper) doesn't matter
+                    $aspNetCore = $xml.SelectSingleNode("//aspNetCore")
+                    if ($null -eq $aspNetCore) {
+                        Write-Error "Could not find aspNetCore element in web.config"
+                        exit 1
+                    }
 
                     # Ensure environmentVariables element exists
-                    if (-not $aspNetCore.environmentVariables) {
+                    $envVarsNode = $aspNetCore.SelectSingleNode("environmentVariables")
+                    if ($null -eq $envVarsNode) {
                         $envVarsNode = $xml.CreateElement("environmentVariables")
                         $aspNetCore.AppendChild($envVarsNode) | Out-Null
                     }
 
                     # Remove existing ASPNETCORE_ENVIRONMENT entry if present
-                    $existing = $aspNetCore.environmentVariables.environmentVariable |
-                        Where-Object { $_.name -eq "ASPNETCORE_ENVIRONMENT" }
-                    if ($existing) { $aspNetCore.environmentVariables.RemoveChild($existing) | Out-Null }
+                    $existing = $envVarsNode.SelectSingleNode("environmentVariable[@name='ASPNETCORE_ENVIRONMENT']")
+                    if ($existing) { $envVarsNode.RemoveChild($existing) | Out-Null }
 
                     # Add fresh entry
                     $envVar = $xml.CreateElement("environmentVariable")
                     $envVar.SetAttribute("name", "ASPNETCORE_ENVIRONMENT")
                     $envVar.SetAttribute("value", "Development")
-                    $aspNetCore.environmentVariables.AppendChild($envVar) | Out-Null
+                    $envVarsNode.AppendChild($envVar) | Out-Null
 
                     $xml.Save($path)
                     Write-Host "web.config patched: ASPNETCORE_ENVIRONMENT=Development"