Disable prefech on links.

[stscoundrel]

Disable prefech on links. Currently majority of links in the site are prefetched on background. While it is generally a very nice behavior, changes in Vercel infra pricing make this uneconomical. Therefore:

• Either use prefetch={false} in links to only fetch them on hover
• Or replace them with plain old a links. Prefetch is pretty much the only advantage of next/link.