release: 22.0.18 depends on zod ^4.6.6

**Problem.** 22.0.17 merged but never published. Its package check (`verify-package.mjs`) requires one zod copy in a clean install for every supported agent-eval minor. This package pinned zod `4.6.7`, while agent-eval 0.221.x pins `4.6.6`, and agent-core 0.13.2 pins `4.6.6` underneath agent-eval 0.222.0 (`4.6.7`). No exact pin can satisfy both minors. Publish run 40301821119: `zod version mismatch: installed=4.6.6 expected=4.6.7`.

Run ID: run_0c34c7b9874c61877f383ecf79a5d29e