Don't load `vite.config.ts` using `import`, rely on `vite.resolveConfig` only

[segevfiner]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the feature has not already been requested

🚀 Feature Proposal

If you currently use a vite.config.ts file, it will fail to load in

fastify-vite/packages/fastify-vite/config.js

Line 286 in 3ba7f29

const resolvedConfig = await resolveConfig(

unless you use a loader that can support loading ts files directly such as tsx, this is not normally a requirement when you otherwise already build your TypeScript and run the built JS with Node. It makes more sense to not require this and rely only on Vite's resolveConfig to load the configuration.

Motivation

Not needing to use tsx to run a project with vite.config.ts that is otherwise already built.

Example

No response