[fix] load data through regular json request

[dummdidumm]

using devalue's stringify/parse methods
Part of #7125 and #6477

Not sure exactly what's left for the above issues to get closed besides allowing setting cache headers again.

If we change to this we could use the same methods for interacting with form actions, allowing them to also return Date objects for example.

Marked as draft, @Rich-Harris feel free to take over/close.

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Latest commit: aa6535f

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[Rich-Harris]

If we change to this we could use the same methods for interacting with form actions, allowing them to also return Date objects for example.

The wrinkle here is that if someone posts to an action manually, they'll get devalue-encoded data in return. We could handle it in SSR and use:enhance but would presumably need to expose something like

import { decode } from '$app/forms';

or, more directly,

import { decode } from 'devalue'; // doesn't currently exist, but decode(obj) would === parse(JSON.stringify(obj))

I think it's fine to merge this as-is then handle headers in a separate PR, so I'm marking this ready

[dummdidumm]

Can't approve because it's my own PR, but consider this an approval in case the answer to my question in the code-comment is "yes".
Edit: Oh and this needs a changeset.

[dummdidumm]

will tree shaking remove the other stuff correctly if we write the import like this?

[Rich-Harris]

Yep, Rollup doesn't care either way

[0gust1]

Thanks, I'll check if it fixes #7203 !

[Tal500]

I'm glad to see this PR fixes a theoretical consideration on a closed issue of mine:
fixes #6466

Worth to mark this issue as "fixed" in the main description of this PR, for automatic referencing to the future.