feat: support setting timeout for client:idle

[ph1p]

Changes

Add the timeout option from the requestIdleCallback specification. https://www.w3.org/TR/requestidlecallback/#the-requestidlecallback-method

Testing

I don't know where to put the test because expanding each file with client directives makes the tests very slow.

{/* Many many components */}
{Array.from({ length: 3000 }).map((_, i) => (<Counter id={`client-idle-${i}`} count={i} client:idle>
	<h1>Hello, client:idle! ${i}</h1>
</Counter>))}

{/* Component loads after a maximum wait of 500ms */}
<Counter id="client-idle-timeout" {...someProps} client:idle={{ timeout: 500 }}>
	<h1>Hello, client:idle={'{{timeout: 500}}'}!</h1>
</Counter>

Docs

client:idle={{timeout}}

Optionally, a value for timeout can be passed to the underlying requestIdleCallback. It hydrates the component if the client is not idle, but specifies the maximum time to wait.

<ShowHideButton client:idle={{ timeout: 500 }} />

withastro/docs#9130

[changeset-bot]

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Latest commit: 062cd46

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[matthewp]

Thanks! Can you add a test? One in the packages/astro/e2e folder would be preferred. I know you can't easily test that it triggers at the timeout, but even adding a test where the option is used will verify that the feature doesn't somehow cause hydration not to occur at all.

[ph1p]

Sure! :)

[ph1p]

Done. I don't know why the PR checks are failing

[bluwy]

I think you can ignore them. Those two don't work well with forks

[sarah11918]

Thanks for this really helpful new feature addition, @ph1p ! I'm sure people will really appreciate this.

I've left some comments below for the changeset for your consideration, and I'll be reviewing the accompanying docs PR shortly!

[github-actions]

This PR is blocked because it contains a minor changeset. A reviewer will merge this at the next release if approved.

[sarah11918]

Approving for docs! Thank you @ph1p !

merge day