Please how can I use the types of a Nitro server route in a declaration file

In the root of my project, I have a

project.d.ts

project.d.ts

which contains all the types used in a Nuxt 3 project. I would like to create a type for the response of

/api/users

/api/users

route which returns

[
  {name: "John Doe", age: 40},
  {name: "Mary Doe", age: 35},
]

[
  {name: "John Doe", age: 40},
  {name: "Mary Doe", age: 35},
]

But I don't know how to do it, here's a reproduction link:
https://codesandbox.io/p/sandbox/loving-hooks-7lci64

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