fix: update sharp to >=0.35.0 to resolve GHSA-f88m-g3jw-g9cj (#21)

Pins sharp via npm overrides to >=0.35.0 to address inherited libvips
vulnerabilities (CVE-2026-33327, CVE-2026-33328, CVE-2026-35590,
CVE-2026-35591). next@15.5.18 constrains sharp to ^0.34.3 so a direct
upgrade is not possible; the override forces 0.35.3.

Co-authored-by: Oz <oz-agent@warp.dev>

Author: independabot-soc2[bot]