Add framework (Next.js, Svelte, SolidJS, etc) specific documentation and not just email provider specific documentation

[spacecat]

Goals

I've read both resend.com docs and react.email docs. None of these do a good job at explaining how to use both Next.js 15+, Resend, and React Email and everything is very confusing and ambiguous.

Sources:

• https://resend.com/nextjs (docs seem old/outdated, uses POST in code example, in other examples GET is used. What should one use? Confusing.)
• https://resend.com/docs/send-with-nextjs (docs + video seem old/outdated - 1 year old video)
• https://react.email/docs/integrations/resend (does not talk about Next.js. npm packages used: resend and @react-email/components. npm package react-email is not needed?!)
• https://react.email/docs/getting-started/manual-setup (npm packages used: react-email and @react-email/components)
• Ambiguous use of react:. Some examples use react: EmailTemplate() and others use react: <EmailTemplate />

There is problabaly some other stuff as well that I forgot to mention but I think you get the point.

And it would probably be a good idea also to add a page for each of the other popular frameworks such as Svelte, Solid, etc

Background

This feature would help developers get up and running more quickly when using Next.js and other frameworks.

Proposal

Go through all Next.js + Resend combination docs on both resend.com and on react.email and make it say the same thing on both places. Also, update the example repos, and explain in more details which npm packages are needed for this combo and why.