[🐞] Type inference for the return type of the `routeLoader$` is skewed.

[genki]

Which component is affected?

Qwik Runtime

Describe the bug

I am making Qwik app that uses the modular-form, I found the route loaders can't be used for the loader option of useForm by type mismatch if their return type are union type.

Here's an example:

export const useFoo = routeLoader$(() => {
  const num = Math.random();
  return num < 0.5 ? true : undefined;
})

export default component$(() => {
  const foo = useFoo();
  type Foo = typeof foo;
  //   ^? type Foo = Readonly<Signal<undefined>> | Readonly<Signal<true>>
  return (

I expected the type of Foo is Readonly<Signal<true|undefined>>.

Reproduction

https://stackblitz.com/edit/github-gerwzj?file=src%2Froutes%2Findex.tsx

Steps to reproduce

No response

System Info

System:
    OS: macOS 14.5
    CPU: (8) arm64 Apple M2
    Memory: 122.13 MB / 24.00 GB
    Shell: 3.6.1 - /opt/homebrew/bin/fish
  Binaries:
    Node: 20.12.1 - /opt/homebrew/opt/node@20/bin/node
    Yarn: 1.22.19 - /opt/homebrew/bin/yarn
    npm: 10.5.0 - /opt/homebrew/opt/node@20/bin/npm
    pnpm: 9.6.0 - ~/Library/pnpm/pnpm
    bun: 1.1.21 - ~/.bun/bin/bun
  Browsers:
    Chrome: 127.0.6533.120
    Safari: 17.5
  npmPackages:
    @builder.io/qwik: link:../test/qwik/packages/qwik => 1.8.0 
    @builder.io/qwik-city: link:../test/qwik/packages/qwik-city => 1.8.0 
    typescript: 5.4.5 => 5.4.5 
    undici: * => 6.19.5 
    vite: ^5.2.10 => 5.3.5

Additional Information

No response

[genki]

This may be a problem of the modular-form.