test(validation): add subject relation format validation and graph depth limit assertions - #3143

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: fusionauth/cla-github-action@58daaf842ac3e26d08c2bdf26770d6e9c5b965a9. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/