[WebAPI] Prototype Prioritized Task Scheduling API

[Rumyra]

Acceptance Criteria

• The listed features are documented sufficiently on MDN
• BCD is updated
• Interactive example and data repos are updated if appropriate
• The content has been reviewed as needed

For folks helping with Firefox related documentation

• Set bugs to dev-doc-complete
• Add entry to Firefox release notes if feature is enabled in release
  or
• Add entry to Firefox experimental features page if feature is not yet enabled in release

Features to document

Prioritized Task Scheduling API

Related Gecko bugs

https://bugzilla.mozilla.org/show_bug.cgi?id=1734997

[hamishwillee]

Explainer: https://github.com/WICG/scheduling-apis / and https://github.com/WICG/scheduling-apis/blob/main/explainers/prioritized-post-task.md

Status:

• BCD
  • FF101 Prioritized Task Scheduling browser-compat-data#16177
  • scheduler global property browser-compat-data#16409
  • TaskSignal: prioritychange_event url fix browser-compat-data#16467
• Docs
  • Prioritized Task Scheduling API #15978
  • Add global scheduler to sidebar Add window.scheduler to Prioritized Task API sidebar #17218
• Experimental features Prioritized Task Scheduling API #15978
• dev-docs-complete

Bulk of the work done. I will add the global scheduler once it is confirmed to be in the right location (by review of the docs). That's a yari task

[hamishwillee]

All done, bar one minor thingy to merge.

[Rumyra]

Nice @hamishwillee

[hamishwillee]

Thanks, great to do something with some "meat" to it. But a bit of a challenge at the time.