Provide warning if store data cannot be serialized by devalue

[ispyinternet]

When you set store data on the server, if it cannot be serialized by devalue (objects containing functions are one such case), your client side will not receive a copy of the store in the init runtime. There are no warnings and for newbies this could be a source of confusion. Suggest a warning message to console server side and possible even set an error message in the store to warn the client side?

[ansarizafar]

We should be able to pass a context object (like Graphql) to page/server routes and components both on server and client. The context object should be available as this.context like this.store. In my opinion its a must have feature.

[dxlbnl]

Here :)

sapper/templates/src/server/middleware/get_page_handler.ts

Lines 320 to 326 in cca417a

	function try_serialize(data: any) {
	try {
	return devalue(data);
	} catch (err) {
	return null;
	}
	}

[PatrickG]

I just stumbled across this issue.
This is fixed.