add auto-close feature

.github/workflows/auto-close.yml

@@ -0,0 +1,35 @@
+name: Close inactive issues and PRs
+on:
+  schedule:
+    - cron: "30 1 * * *"
+
+jobs:
+  close-issues:
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      # https://github.com/marketplace/actions/close-stale-issues
+      - uses: actions/stale@v5
+        with:
+          any-of-issue-labels: waiting-for-customer
+          stale-label: stale
+          exempt-pr-labels: exempt
+          exempt-issue-labels: exempt
+          days-before-issue-stale: 14
+          days-before-issue-close: 14
+          stale-issue-message: |
+            This issue is stale because it has been open for 14 days with no response
+            from the reporter.  It will be automatically closed in 14 days from this message.
+          close-issue-message: |
+            This issue was closed because it has been inactive for 28 days.
+          stale-pr-message: |
+            This PR is stale because it has been open for 30 days with no activity.
+            It will be automatically closed in 30 days from this message.
+          close-pr-message: |
+            This PR was closed because it has been inactive for 60 days.
+          days-before-pr-stale: 30
+          days-before-pr-close: 30
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          # debug-only: false