chore: setup stale workflow

.github/workflows/stale.yml

@@ -0,0 +1,21 @@
+name: Stale
+
+on:
+  schedule:
+    - cron: 30 7 * * *
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v4
+        with:
+          stale-issue-label: stale
+          stale-issue-message: |
+            This issue is stale because it has been open 15 days with no activity.
+            Remove stale label or comment or this will be closed in 5 days.
+          close-issue-message: |
+            This issue was closed because it has been stalled for 5 days with no activity.
+          days-before-issue-stale: 15
+          days-before-issue-close: 5
+          any-of-labels: awaiting feedback