Convex 1.49.0 sharpens validators, agent tooling

This is a pragmatic release that makes Convex safer for callback-heavy backends while positioning it directly inside agent-driven development workflows.

• –`v.function()` improves runtime validation for function handles passed through Convex APIs.
• –Native Claude Code and Codex plugins bring Convex skills, MCP access, specialized agents, and error monitoring into coding workflows.
• –The Node 20 cutoff is operationally important: update local environments, CI images, and deployment pipelines before upgrading.
• –Convex is increasingly treating AI agents as first-class developers, not just another application feature.