feat: add bulk merge pr workflow

.github/workflows/bulk-merge-prs.yaml

@@ -0,0 +1,54 @@
+---
+  # yaml-language-server: $schema=https://json.schemastore.org/github-workflow.json
+  name: "Bulk Merge PRs"
+
+  on:
+    workflow_dispatch:
+      inputs:
+        dryRun:
+          description: Dry Run
+          default: "false"
+          required: false
+        labels:
+          description: Labels
+          default: "any"
+          required: false
+
+  jobs:
+    bulk-merge-prs:
+      name: Bulk Merge PRs
+      runs-on: ubuntu-latest
+      steps:
+        - name: Generate Token
+          uses: actions/create-github-app-token@v1
+          id: app-token
+          with:
+            app-id: "${{ secrets.BOT_APP_ID }}"
+            private-key: "${{ secrets.BOT_APP_PRIVATE_KEY }}"
+
+        - name: Checkout
+          uses: actions/checkout@v4
+          with:
+            token: "${{ steps.app-token.outputs.token }}"
+
+        - name: Merge
+          shell: bash
+          env:
+            GITHUB_TOKEN: "${{ steps.app-token.outputs.token }}"
+          run: |
+            args=()
+            args+=(--app ${{ secrets.BOT_USERNAME }})
+            args+=(--state open)
+            if [ "${{ github.event.inputs.labels }}" != "any" ]; then
+                IFS=',' read -ra labels <<< "${{ github.event.inputs.labels }}"
+                for label in "${labels[@]}"; do
+                    args+=(--label "${label}")
+                done
+            fi
+            for id in $(gh pr list "${args[@]}" --jq '.[].number' --json number); do
+                if [ "${{ github.event.inputs.dryRun }}" = "true" ]; then
+                    echo "Dry run: gh pr merge $id --squash"
+                    continue
+                fi
+                gh pr merge "${id}" --squash
+            done