Fix issue importing local TS files

[simonsmith]

Based on the fix discovered by @patheticGeek in this discussion I've applied the same one here.

Running the test project in this comment now works as expected

fixes #21

[simonsmith]

I've had a bit more a play with this, and I think this package needs more love in general to support Astro 5. So could be worth addressing that to begin with

[NikitaIT]

Fastify should be "pre-middleware", not "post-middleware".

It breaks rest api design in general. This no longer works:

fastify.post('/login', () => 'fastify')
await fetch("http://localhost:4321/login", { method: "GET" }).then(x => x.text()) // .astro
await fetch("http://localhost:4321/login", { method: "POST" }).then(x => x.text()) // fastify

Because .astro matches only by URI, and fastify matches by any HTTP.

Maybe there is another solution.

Btw, it looks like code transformer / module resolution problem, so if it needs to be fixed by middleware reordering it most likely needs to be fixed in Vite or there should be the way to say "do after transform" or smth.