Native config loader based on oxnode ability #3380

--configLoader native is about to become the default config loading method in Vite 9+.

After that, some syntax like __dirname and TypeScript enum in Vite config and would become incompatible. For pure Vite, supporting these syntax means adding oxnode or jiti dependencies, which increases its size.

But Vite+ is different, vpx already included oxnode, there is also a module vite-plus/register for adding TypeScript loading ability for Node. In other words, Vite+ already has the ability that jiti provides.

So in the future version where native become the default config loader, in order to have better compatibility, it might be a good idea to try using oxc-transformer's ability to load config, which costs little on Vite+. (provide jiti-like ability)

Not sure if we should start this experiment before Vite 9+ (config loader performance improvement #2698)