Explain why the auto-merge dispatches deploy.yml

.github/workflows/deploy.yml

@@ -96,6 +96,11 @@ jobs:
             sleep 15
           done
           [ -n "$merged" ] || { echo "::error::gate passed but the squash merge did not land after 3 attempts; the bump is unmerged and no deploy was dispatched"; exit 1; }
+          # A merge made with GITHUB_TOKEN raises no push event -- GitHub suppresses
+          # them so workflows cannot retrigger themselves -- so deploy would never run
+          # and the site would keep serving the previous build. Ask for it explicitly;
+          # a workflow_dispatch through the API is not suppressed. The dispatched run
+          # is the same gate-then-deploy pipeline, so a bad merge still ships nothing.
           gh workflow run deploy.yml --repo "$GITHUB_REPOSITORY" --ref main
         env:
           PR_URL: ${{ github.event.pull_request.html_url }}