chore(deps): bump unpdf from 1.6.2 to 1.8.1

[dependabot]

Bumps unpdf from 1.6.2 to 1.8.1.

Release notes

Sourced from unpdf's releases.

v1.8.1

   🐞 Bug Fixes

• Polyfill Math.sumPrecise for PDF.js  -  by @​tra0x in unjs/unpdf#64 (a6ae8)

    View changes on GitHub

v1.8.0

   🚀 Features

• Upgrade to PDF.js v6.1  -  by @​johannschopplich in unjs/unpdf#62 (bbe69)
• Support @napi-rs/canvas v1  -  by @​johannschopplich (933ec)

   🏎 Performance

• Migrate build tooling to tsdown and rolldown  -  by @​johannschopplich in unjs/unpdf#63 (3f591)

    View changes on GitHub

v1.7.0

   🐞 Bug Fixes

• Add cMapUrl for CJK font support in Node.js  -  by @​xieguaiwu in unjs/unpdf#52 (3789c)
• Add .js extension to relative imports in .d.mts & .d.cts files  -  by @​kumarchandresh in unjs/unpdf#56 (10e6d)
• Resolve @napi-rs/canvas in the bundled PDF.js canvas factory  -  by @​drakosha in unjs/unpdf#54 (f5406)
• Preserve line breaks in extractText with mergePages  -  by @​dsfaccini in unjs/unpdf#58 (a49be)
• Destroy internally created document proxies and canvas resources  -  by @​dsfaccini in unjs/unpdf#57 (ed9ac)

   🏎 Performance

• Encode PNG bytes directly in renderPageAsImage  -  by @​johannschopplich and @​dsfaccini in unjs/unpdf#60 (95ebf)

    View changes on GitHub

Commits

• 4bc3080 chore: release v1.8.1
• a6ae87f fix: polyfill Math.sumPrecise for PDF.js (#64)
• f6c2fca docs: tighten the code comments
• 704d56e chore: release v1.8.0
• e3d0da6 chore: upgrade dependencies
• 933ec46 feat: support @napi-rs/canvas v1
• 7096a1f chore: update dependencies
• 3f59194 perf: migrate build tooling to tsdown and rolldown (#63)
• bbe698d feat: upgrade to PDF.js v6.1 (#62)
• 5125d67 chore: release v1.7.0
• Additional commits viewable in compare view