chore(deps-dev): bump dependencies (#1407)

- @astrojs/check              ^0.9.4  →   ^0.9.5
- @astrojs/vercel            ^8.2.10  →   ^9.0.0
- astro                      ^5.14.5  →  ^5.15.2
- starlight-blog             ^0.24.2  →  ^0.24.3
- starlight-links-validator  ^0.18.0  →  ^0.19.0
- starlight-showcases         ^0.3.0  →   ^0.3.1
- vercel                     ^48.3.0  →  ^48.6.6
- vitest                      ^3.2.4  →   ^4.0.4

Author: julien-deramond