Add scheduled subset sync workflow

.gitea/workflows/sync-subset.yml

@@ -0,0 +1,20 @@
+name: sync-ios-rule-subset
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: '0 */12 * * *'
+jobs:
+  sync:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Sync subset from upstream
+        env:
+          GITEA_REPO_OWNER: yuanzhen869
+          GITEA_REPO_NAME: ios-rule-script-subset
+          GITEA_SYNC_USERNAME: yuanzhen869
+          GITEA_SYNC_EMAIL: yuanzhen869@gmail.com
+          GITEA_SYNC_TOKEN: ${{ secrets.SYNC_TOKEN }}
+        run: |
+          bash ./scripts/sync_subset.sh