Feature Request: Let `open` argument open a relative URL

[atomflunder]

Describe the feature

Hi, and thanks for this great tool!

When I open my nuxt dev server with npn run dev --open, I often want to navigate to a specific URL right away, and not wait for my browser to open up and then manually type in the URL.

My feature request is that the open argument is changed from boolean to instead be string, or boolean | string, appending the argument to the baseURL before opening it.

Example of what I mean:

npm run dev --open myPage

would open http://localhost:3000/myPage.

Is this wanted? If so, I could begin to work on it myself.

Additional information

• [x] Would you be willing to help implement this feature?