introducing stalebot to help clean up old issues

Signed-off-by: si458 <simonsmith5521@gmail.com>

.github/workflows/stale.yml

@@ -0,0 +1,33 @@
+name: "Close stale issues and PRs"
+on:
+  schedule:
+    - cron: "1 2 * * *"
+  workflow_dispatch:
+
+permissions:
+  actions: write
+  contents: write
+  issues: write
+  pull-requests: write
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/stale@v9
+      with:
+        # Issues configuration
+        stale-issue-message: "This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions."
+        close-issue-message: "This issue has been automatically closed due to inactivity. If you believe this is still relevant, please feel free to reopen it."
+        
+        # PRs configuration
+        stale-pr-message: "This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions."
+        close-pr-message: "This pull request has been automatically closed due to inactivity. If you'd like to continue working on it, please reopen it."
+        
+        # Common configuration
+        exempt-issue-labels: "pinned,important"
+        exempt-pr-labels: "pinned,important"
+        
+        # Other configurations
+        exempt-draft-pr: true
+        operations-per-run: 100