Add AI-generated PR labeling workflow (#491)

Author: iainbreen

.github/workflows/label-ai-generated-prs.yml

@@ -0,0 +1,11 @@
+# .github/workflows/label-ai-generated-prs.yml
+name: Label AI-generated PRs
+
+on:
+  pull_request:
+    types: [opened, edited, synchronize]   # run when the body changes too
+
+jobs:
+  call-label-ai-prs:
+    uses: intercom/github-action-workflows/.github/workflows/label-ai-prs.yml@main
+    secrets: inherit