fix: use null-safe CompletableFutures.awaitWithCheckCanceled wrapper to prevent NPE when future is null - #1663

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: amannn/action-semantic-pull-request@d2ab30dcffc66150340abb5b947d518a3c3ce9cb. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/