Support vite(6) as config loader

[pi0]

Describe the feature

(context: quickly talking with @yyx990803)

Vite 6 with environment API allows loading ts config files similar to jiti.

We can optionally support vite as a config loader for .ts support, faster resolutions, custom plugins, etc.

/cc @danielroe @antfu @patak-dev would love to hear your early thoughts!

Additional information

• Would you be willing to help implement this feature?

[patak-dev]

cc @sheremet-va

• feat: use module runner to import the config vitejs/vite#18637

[sheremet-va]

We had an idea to expose this as a function like “import” (inlines the environment when called, not good for performance or memory to be honest 👀) and possibly introduce “vite run” command in the future.

[pi0]

@sheremet-va Maybe it could be coupled with an unimport() API (mimicking clear require.cache) that allows to free-up memory? We probably need something similar to also allow reloading config same as jiti with disabled cache.