* chore: upgrade Next.js in evals/visualizer from 16.1.4 to 16.2.6
Resolves multiple security advisories in Next.js 16.1.4 including
middleware/proxy bypass, SSRF, DoS, and XSS issues. The evals
visualizer is an internal dev tool with no external exposure, but
keeping dependencies current reduces supply-chain risk.
* fix: remove redundancy in choice of package manager to avoid drift
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Co-authored-by: Abhishek Kumar <abhishek@a6k.me>