[Blocker] fix: resolve Vercel build error - downgrade eslint-config-next

## GitHub Update **Repository:** [MKWcorp/sales-race-beautycenter](https://github.com/MKWcorp/sales-race-beautycenter) **Author:** MKWcorp **Date:** 1/7/2026, 4:48:44 AM **Commit:** [`15d0d18`](https://github.com/MKWcorp/sales-race-beautycenter/commit/15d0d186a230d5c24fe5330bfbaf16888c018176) ### Commit Message fix: resolve Vercel build error - downgrade eslint-config-next - Downgrade eslint-config-next from 16.1.1 to 14.2.35 for compatibility - eslint-config-next 16.x requires eslint >=9, but we use eslint 8.x - Add .npmrc with legacy-peer-deps=true for Vercel builds - Keep Next.js at 14.2.35 (security patched version) - Fixes ERESOLVE peer dependency conflict on Vercel deployment --- _This story was imported from historical commits._