Add automatic issue close mechanism

.github/workflows/stale.yml

@@ -0,0 +1,16 @@
+name: 'Close stale issues'
+on:
+  schedule:
+    - cron: '30 3 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v9
+        with:
+          any-of-labels: 'stale'
+          days-before-stale: -1
+          days-before-close: 7
+          days-before-pr-close: -1
+          close-issue-message: 'This issue was closed because it has been stalled for 7 days with no activity.'