Implemented autosave on a 5-second timer

[Levi-Lesches]

Fixes #2871 by saving the editor content to local storage under they key user_input every 5 seconds, and in dispose

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[Levi-Lesches]

@parlough I fixed the double quotes

[parlough]

Sweet! Thanks so much for implementing this again :D

[parlough]

Do you think it's worth it to convert this fallback to a callback, so we don't unnecessarily retrieve the old snippet?

[Levi-Lesches]

I think ?? is short circuiting, so it should be fine? EDIT: Just checked, it is

[Levi-Lesches]

Oh, if you meant not retrieving the old snippet or user input in case a gist id or otherwise is provided.

I tried making it a callback, and got some very strange errors on the web side. Each time I restarted, it was that JS can't read some property, but it was a different property each time. Once it didn't even let the flutter tool connect because the bootstrapper got stuck. Not sure what's up with that but I'll leave the PR as-is for now

[Levi-Lesches]

@parlough Any updates?

[Levi-Lesches]

Sorry for the annoying pings, just want to make sure this doesn't slip between the cracks

[parlough]

@Levi-Lesches Sorry for the delay, I've been away.

The change looks good to me, but before landing, we need to wait for others to determine DartPad's storage policies and how we will inform users of them.

I'll land this PR when able and ping you if any changes are needed.

Thanks again!

[Levi-Lesches]

Hi @parlough, any updates?