test(agents): cover tool frontmatter parsing contract - #1144

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5, actions/setup-go@d35c59abb061a4a6fb18e82ac0862c26744d6ab5, actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/