chore(repo): Dispatch new-release to www.trigger.dev repo to generate version changelog draft PR (#3162)

.github/workflows/release.yml

@@ -194,6 +194,21 @@ jobs:
 
           gh release edit "${TAG}" --notes-file /tmp/release-body.md
 
+  # Dispatch changelog entry creation to the marketing site repo.
+  # Runs after update-release so the GitHub release body already has the exact Docker image URL.
+  dispatch-changelog:
+    name: 📝 Dispatch changelog PR
+    needs: [release, update-release]
+    if: needs.release.outputs.published == 'true'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: peter-evans/repository-dispatch@v3
+        with:
+          token: ${{ secrets.CROSS_REPO_PAT }}
+          repository: triggerdotdev/trigger.dev-site-v3
+          event-type: new-release
+          client-payload: '{"version": "${{ needs.release.outputs.published_package_version }}"}'
+
   # The prerelease job needs to be on the same workflow file due to a limitation related to how npm verifies OIDC claims.
   prerelease:
     name: 🧪 Prerelease