on-demand cache revalidation/incremental static genration

Describe the feature

Hi!
The feature is to add a global function revalidate which can be called with path argument to revalidate the cache of a specific path. Ex: Initially route have {static:true} and in API route we can do revalidate('/blog'), revalidate('/blog/posts/1').

It will be useful for CMS and can be used with webhook to see instant changes.

This feature can further be extended in nuxt for on-demand incremental static generation.

This can be further simplified by providing a default route /__nuxt/revalidate/ or '__nitro/revalidate' with path='...' to revalidate the route. Of course, user can add middleware to secure the route to verify the request is coming from CMS.

Additional information

• Would you be willing to help implement this feature?

Start by reviewing the existing API route handling and static-generation cache behavior. Compare the proposed global revalidate(path) function with the optional /__nuxt/revalidate or /__nitro/revalidate route. Done means a specified path can be revalidated on demand, including from a secured CMS webhook.