Summary

This PR adds support for webpackPrefetch and webpackPreload magic comments for new Worker() chunks, addressing issue #19373.

Currently, dynamic imports support webpackPrefetch and webpackPreload magic comments to hint the browser to prefetch/preload chunks for better performance. This PR extends the same functionality to Worker chunks.

Example usage:

const worker = new Worker(
  /* webpackPrefetch: true */
  new URL("./worker.js", import.meta.url)
);

const worker2 = new Worker(
  /* webpackPreload: 5 */
  new URL("./heavy-worker.js", import.meta.url)
);

Closes #19373

What kind of change does this PR introduce?

feat - New feature extending prefetch/preload support to Worker chunks

Did you add tests for your changes?

Yes, added test case in test/configCases/worker/worker-prefetch-preload/:

• should support webpackPrefetch for Worker
• should support webpackPreload for Worker
• should support webpackPrefetch with numeric order for Worker
• should support webpackPreload with numeric order for Worker

Does this PR introduce a breaking change?

No. This is an additive feature using existing magic comment syntax.

If relevant, what needs to be documented once your changes are merged or what have you already documented?

Documentation should be updated to mention that webpackPrefetch and webpackPreload magic comments now work with new Worker() syntax, similar to dynamic import().