feat: Add eagerness support for prefetch()

[Marocco2]

Changes

• What does this change?

New PrefetchOptions param eagerness that can be explicitly stated for prefetch() function.

Usecase: letting a browser manage when a page should be prerendered will simplify web site code compared to default behavior (no eagerness passed will automatically default to immediate, causing headcaches if you want to use FIFO strategy available for moderate and conservative args)

Reference doc: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/script/type/speculationrules#eagerness

Testing

No tests added, as there weren't for PrefetchOptions

Docs

/cc @withastro/maintainers-docs

prefetch() doc should be updated accordingly to notify users a new option to be passed on

[changeset-bot]

🦋 Changeset detected

Latest commit: 01ee0d0

The changes in this PR will be included in the next version bump.

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[codspeed-hq]

CodSpeed Performance Report

Merging #13405 will not alter performance

_{Comparing Marocco2:feat/prefetch-eagerness (01ee0d0) with main (7185491)}

Summary

✅ 6 untouched benchmarks

[ematipico]

Thank you for your contribution @Marocco2. This is a new feature, so it requires some updates in our docs. Can you do that? Let us know if you have time, we plan a release next week

[Marocco2]

Thank you for your contribution @Marocco2. This is a new feature, so it requires some updates in our docs. Can you do that? Let us know if you have time, we plan a release next week

Thanks for replying! I'll check in these days what to do. Do you have any pipelines on how to add docs?

[ematipico]

Docs PR should be sent to withastro/docs repository. This is the page you want to update: https://docs.astro.build/en/guides/prefetch/

[Marocco2]

Added docs here: withastro/docs#11250
Hopefully I'll get required changes ASAP

[github-actions]

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

[sarah11918]

Thank you for contributing this feature! I'm sure people will appreciate this new option!

Here's my suggestion for an updated changeset based on the final docs. (Note that it doesn't have to be identical to docs, or explain the whole feature in detail -- usually it focuses more on the benefits, and gives people enough information to know whether they are interested in learning more).

Take from it what you like!

[sarah11918]

Approving for docs, assuming nothing changes in the feature! (Docs PR is all approved and ready to go, too.) 🚀

[ematipico]

Thank you @Marocco2

merge day