Add stale issues workflow

Author: GeiserX

.github/workflows/stale.yml

@@ -0,0 +1,19 @@
+name: Close stale issues
+on:
+  schedule:
+    - cron: '0 0 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v9
+        with:
+          stale-issue-message: 'This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs.'
+          close-issue-message: 'This issue was closed because it has been stale for 14 days with no activity.'
+          days-before-issue-stale: 14
+          days-before-issue-close: 14
+          stale-issue-label: 'stale'
+          exempt-issue-labels: 'pinned'
+          days-before-pr-stale: -1
+          days-before-pr-close: -1