Figure out a way to have a virtual module import another virtual module

[NullVoxPopuli]

Right now, folks have to do this in their apps:

await this.docs.setup({
  apiDocs: await import('kolay/api-docs:virtual'),
  manifest: await import('kolay/manifest:virtual'),
  resolve: {
    'my-library': await import('my-library'),
    'something-else': await import('something-else'),
  },
});

This isn't great because:

• it's a bit of ceramony
• two imports instead of one
• two minimum properties, ideal would be 0 (resolve is optional)

previously issues that are now non issues

• TS does not support resolving paths with colons microsoft/TypeScript#57529~~

If we can shorten this down to a single import, the whole thing could be:

import { setupKolay } from 'kolay/setup'; // a virtual module

// ...
const manifest = await setupKolay({
  resolve: {
    'my-library': await import('my-library'),
    'something-else': await import('something-else'),
  },
});

which, I think, makes more sense, and kolay/setup is easy to provide type definitions for.

But, so far, a virtual module cannot import another virtual module, because plugins' resolve hooks are only used when resolving from the consuming app and a virtual module is kind of in a void of its own.

[NullVoxPopuli]

Potentially possible after: unjs/unplugin#374