ci: weekly auto-merge of Dependabot PRs (#59)

Author: raphael

.github/workflows/dependabot-weekly-automerge.yml

@@ -0,0 +1,24 @@
+name: Weekly auto-merge Dependabot PRs
+on:
+  schedule:
+    - cron: '0 6 * * 1'
+  workflow_dispatch:
+permissions:
+  contents: write
+  pull-requests: write
+jobs:
+  automerge:
+    runs-on: ubuntu-latest
+    env:
+      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    steps:
+      - uses: actions/checkout@v5
+      - name: Merge clean Dependabot PRs
+        run: |
+          set -euo pipefail
+          prs=$(gh pr list --state open --search 'author:app/dependabot' --json number,mergeStateStatus -L 200 \
+                | jq -r '.[] | select(.mergeStateStatus=="CLEAN") | .number')
+          for n in $prs; do
+            echo "Enabling auto-merge for #$n"
+            gh pr merge "$n" --squash --auto --delete-branch || true
+          done