Add issue management workflow

Stale in 7 days + close in 3 days.

.github/workflows/stale.yml

@@ -0,0 +1,33 @@
+# This workflow warns and then closes issues and PRs that have had no activity for a specified amount of time.
+#
+# You can adjust the behavior by modifying this file.
+# For more information, see:
+# https://github.com/actions/stale
+name: Mark stale issues and pull requests
+
+on:
+  schedule:
+  - cron: '0 0 * * *'
+
+jobs:
+  stale:
+
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      pull-requests: write
+
+    steps:
+    - uses: actions/[email protected]
+      with:
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+        stale-issue-message: 'Stale due to inactivity. Closing in 3 days if no further activities.'
+        close-issue-message: 'Close due to inactivity'
+        stale-issue-label: 'no-issue-activity'
+        days-before-pr-stale: -1
+        days-before-issue-stale: 7
+        days-before-issue-close: 3
+        exempt-issue-assignees: true
+
+
+