Establish clean homelab infrastructure baseline

Reorganize the brownfield repository, remove retired and generated artifacts, harden ignore rules, and record the GitOps/IaC redesign.

apps/smtp-relay/scripts/enable-smtp-auth.ps1

@@ -0,0 +1,19 @@
+# Enables Authenticated SMTP (SMTP AUTH) on [email protected] so OAuth SMTP works.
+# Run it yourself (interactive admin device-login):
+#     ! pwsh ~/services/apps/smtp-relay/scripts/enable-smtp-auth.ps1
+# At the prompt, open https://microsoft.com/devicelogin and sign in as a tenant ADMIN.
+param(
+  [string]$Mailbox = '[email protected]'
+)
+Import-Module ExchangeOnlineManagement
+Connect-ExchangeOnline -Device -ShowBanner:$false
+
+$mbx = Get-CASMailbox -Identity $Mailbox -ErrorAction SilentlyContinue
+if (-not $mbx) {
+  Write-Host "Mailbox '$Mailbox' isn't provisioned yet (licensing can take a few minutes). Wait and re-run."
+} else {
+  Set-CASMailbox -Identity $Mailbox -SmtpClientAuthenticationDisabled:$false
+  Write-Host "== Authenticated SMTP status =="
+  Get-CASMailbox -Identity $Mailbox | Format-List Name, SmtpClientAuthenticationDisabled
+}
+Disconnect-ExchangeOnline -Confirm:$false