Enhance GitHub Actions workflow: Add pull request trigger and secret management for project integration

.github/workflows/add-to-project.yml

@@ -3,12 +3,33 @@ on:
   issues:
     types:
       - opened
+  pull_request:
+    types:
+      - opened
+
+permissions:
+  contents: read
+  id-token: write
+
 jobs:
   add-to-project:
     name: Add issue to project
     runs-on: ubuntu-latest
     steps:
+      - id: get-secrets
+        uses: grafana/shared-workflows/actions/get-vault-secrets@main
+        with:
+          repo_secrets: |
+            GITHUB_APP_ID=grafana-oss-big-tent:app-id
+            GITHUB_APP_PRIVATE_KEY=grafana-oss-big-tent:private-key
+      - name: Generate a token
+        id: generate-token
+        uses: actions/create-github-app-token@v1
+        with:
+          app-id: ${{ env.GITHUB_APP_ID }}
+          private-key: ${{ env.GITHUB_APP_PRIVATE_KEY }}
+          owner: ${{ github.repository_owner }}
       - uses: actions/add-to-project@main
         with:
           project-url: https://github.com/orgs/grafana/projects/457
-          github-token: ${{ secrets.ISSUE_COMMANDS_TOKEN }}
+          github-token: ${{ steps.generate-token.outputs.token }}