Dynamic update

Describe the problem

Sometimes the changes in the new version are so minor that updating the page and all the resources to apply them is very inefficient.
I suggest creating a dynamic update feature similar to hot reload.

Describe the proposed solution

The idea is very crude.

I suggest:

• plan_dynamic_update - a function that will schedule dynamic_update to run on navigation
• dynamic_update - a function that triggers a dynamic update

Dynamic update:

1. a certain manifest is updated
2. it is compared with the current version manifest
3. only the modified parts of the application are updated
   • static assets are being reloaded
   • sw is being updated (https://github.com/sveltejs/kit/issues/3667)
   • server side and endpoints with load dependencies are updated, live connections are not interrupted
   • components are being updated, other components are not affected and their state does not change
     • for example, the page component has changed, it is being reloaded, but the layout component is not affected, as if normal navigation had occurred
     • for example, a component has changed in the depth of the page, and if the component is usually imported and treated as a constant, now it becomes a reactive variable and restarts the dependent code when updating

It seems like it's going to be difficult or impossible.

Alternatives considered

No response

Importance

nice to have

Additional Information

https://rauchg.com/2014/7-principles-of-rich-web-applications#push-code-updates
https://github.com/gaearon/react-hot-loader/issues/38

Start by breaking down the proposed plan_dynamic_update and dynamic_update entry points and reviewing the linked service-worker issue (#3667). Define how manifest comparison, asset and service-worker updates, server-side dependencies, and component state preservation would work; done would require an agreed design and implementation scope.