Get assets full URL or trigger handle for fetch(asset)

Describe the problem

Expose a way in handle to get access to the final deployed path of assets. This will allow things like on the fly image optimisation.

Describe the proposed solution

hooks.server.ts can have a new method handleAssets, or can augment existing method

If you do a fetch('/image.png'), it triggers handleAssets, provides it with the full path to that image. With which I can return a custom response. handleAssets could be used to use sharp on the image on the fly, so inherently making SSR'd image optimisation a reality, like Nuxt Image

Would it be slower than static optimisation? Yes, but sometimes you just cannot optimise early, and the server costs may not matter as much

Alternatives considered

1. Do nothing

Importance

would make my life easier

Additional Information

No response

Start with hooks.server.ts and trace how fetch('/image.png') is handled for deployed assets. Clarify the API shape for handleAssets, including access to the final asset path and the ability to return a custom response. Done means the behavior and response contract are documented and covered by relevant tests.