enable actions/stale to close issues and PRs. (#80)

Signed-off-by: Tomoya.Fujita <Tomoya.Fujita@sony.com>

Author: fujitatomoya

.github/workflows/stale.yml

@@ -0,0 +1,57 @@
+name: 'Close stale issues and PRs'
+
+on:
+  schedule:
+    # Run daily at 1:30 AM UTC
+    - cron: '30 1 * * *'
+  workflow_dispatch: # Allow manual triggering
+
+permissions:
+  issues: write
+  pull-requests: write
+
+jobs:
+  stale:
+    name: 'Mark and close stale issues and PRs'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v10
+        with:
+          # Stale configuration
+          days-before-stale: 90
+          days-before-close: 60
+
+          # Labels
+          stale-issue-label: 'stale'
+          stale-pr-label: 'stale'
+          exempt-issue-labels: 'help-wanted,good-first-issue,pinned'
+          exempt-pr-labels: 'help-wanted,good-first-issue,pinned'
+
+          # Exemptions
+          exempt-all-issue-assignees: true
+          exempt-all-pr-assignees: true
+          exempt-all-issue-milestones: true
+          exempt-all-pr-milestones: true
+
+          # Issue messages
+          stale-issue-message: |
+            Hello 👋 Looks like there was no activity on this issue for the last 90 days.
+            **Do you mind updating us on the status?** Is this still reproducible or needed? If yes, just comment on this issue or push a commit. Thanks! 🤗
+            If there will be no activity for 60 days, this issue will be closed (we can always reopen an issue if we need!).
+
+          close-issue-message: |
+            Closing for now as there was no activity for the last 60 days after being marked as stale, let us know if you need this to be reopened! 🤗
+
+          # PR messages
+          stale-pr-message: |
+            Hello 👋 Looks like there was no activity on this amazing PR for the last 90 days.
+            **Do you mind updating us on the status?** Is there anything we can help with? If you plan to still work on it, just comment on this PR or push a commit. Thanks! 🤗
+            If there will be no activity for 60 days, this PR will be closed (we can always reopen a PR if you get back to this!).
+
+          close-pr-message: |
+            Closing for now as there was no activity for the last 60 days after being marked as stale, let us know if you need this to be reopened! 🤗
+
+          # Operations and behavior
+          operations-per-run: 100
+          ascending: true
+          remove-stale-when-updated: true