github: add workflow action

.github/workflows/stale.yml

@@ -0,0 +1,26 @@
+name: Close manually marked stale issues
+on:
+  schedule:
+    - cron: "30 12 * * *"  # 每天 UTC 12:30 运行
+
+jobs:
+  close-issues:
+    runs-on: ubuntu-latest
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      - uses: actions/stale@v9
+        with:
+          # 禁用自动标记 stale（仅手动标记的 issue 会被处理）
+          days-before-issue-stale: -1
+          # 手动标记后，14 天后关闭
+          days-before-issue-close: 14
+          # 使用的标签（必须和你手动添加的标签一致）
+          stale-issue-label: "stale"
+          # 关闭时的提示信息
+          close-issue-message: "This issue was closed because it was marked as stale and had no activity for 14 days."
+          # 禁用 PR 处理
+          days-before-pr-stale: -1
+          days-before-pr-close: -1
+          repo-token: ${{ secrets.GITHUB_TOKEN }}