add stale action

.github/workflows/stale.yml

@@ -0,0 +1,41 @@
+name: 💤 Stale
+
+on:
+  schedule:
+    - cron: '0 0 * * 0' # Weekly
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    permissions:
+      actions: write
+      contents: write # only for delete-branch option
+      issues: write
+      pull-requests: write
+    steps:
+      - uses: actions/stale@v10
+        with:
+          days-before-stale: 90
+          days-before-close: 7
+          stale-issue-label: "Status: Stale"
+          stale-pr-label: "Status: Stale"
+          stale-issue-message: >
+            This issue has been automatically marked as stale because it has not
+            had recent activity. It will be closed in 7 days if no further
+            activity occurs. Thank you for your contributions!
+          stale-pr-message: >
+            This pull request has been automatically marked as stale due to
+            inactivity. It will be closed in 7 days if no further activity
+            occurs. Please update if you wish to keep it open.
+          close-issue-message: >
+            This issue has been automatically closed due to inactivity. If you
+            think this is a mistake or would like to continue the discussion,
+            please comment or feel free to reopen it.
+          close-pr-message: >
+            This pull request has been automatically closed due to inactivity.
+            If you think this is a mistake or would like to continue working on
+            it, please comment or feel free to reopen it.
+          close-issue-label: "Status: Abandoned"
+          close-pr-label: "Status: Abandoned"
+          exempt-issue-labels: "Status: Abandoned"
+          exempt-pr-labels: "Status: Abandoned"