[26.0] Ignore aborted requests in rethrowSimple

[mvdbeek]

When the browser aborts a request (e.g. during page navigation), silently return from rethrowSimple instead of throwing. No downstream consumer will handle the result when the page is being torn down.

Fixes GALAXY-MAIN-4KSCZZZ0014Z6 / #22324

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• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.

[github-actions]

This PR was merged without a "kind/" label, please correct.

[dannon]

This looks good and the intent makes sense, but Claude flagged something worth thinking about -- rethrowSimple returns never, and every caller in the codebase relies on that for control flow narrowing. The pattern everywhere is:

const { data, error } = await GalaxyApi().GET(...)
if (error) {
    rethrowSimple(error);
}
return data.map(...)  // TS knows data isn't undefined because rethrowSimple never returns

With the return undefined as never, if an abort happens, execution falls through and data is undefined, so you'd get a TypeError instead of the clean silent swallow. During full page teardown that's probably fine since nobody's around to care, but ERR_CANCELED also fires during SPA route changes when components unmount their AbortControllers -- where the app keeps running and that TypeError is arguably worse than the original error.

Might be better to handle this at a higher level so the never contract stays intact -- something like an isAbortedRequest check callers can use before calling rethrowSimple, or an interceptor that swallows aborts before they reach application code.