Add a Github Actions script that synchronizes the template every month.

.github/workflows/sync.yml

@@ -0,0 +1,37 @@
+name: Sync branch to template
+
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: '14 0 1 * *'
+
+jobs:
+  sync:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Sync branch to template
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          branch_name=$(git rev-parse --abbrev-ref HEAD)
+          original_remote=$(git remote get-url origin)
+          pr_branch="sync/${branch_name}"
+          git config --global user.email "github-actions[bot]@users.noreply.github.com"
+          git config --global user.name "github-actions[bot]"
+          git remote add template https://github.com/ubiquity/ts-template
+          git fetch template development
+          git update-index --assume-unchanged ".github/workflows/sync.yml"
+          git merge template/development --allow-unrelated-histories || true
+          git checkout -b "$pr_branch"
+          git add .
+          git push "$original_remote" "$pr_branch"
+          gh pr create --title "Sync branch to template" --body "This pull request merges changes from the template repository." --head "$pr_branch" --base "$branch_name"
+