chore: fix server fetch test setup

[elliott-with-the-longest-name-on-github]

The newly ported self-fetch redirect tests call set_options, which was removed from version-3 in #17008. The suite fails during setup before any of its six regression tests run, as seen in the checks on #17288.

Provide options through the generated-server mock instead, matching the current runtime. Also formats one overlong import in the recently added action tests. No runtime changes or changeset. Verified the failure before the fix; afterward all six regression tests and all 77 Kit unit-test files pass (1,053 tests, 110 skipped), along with format, lint, and full typechecking.

[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from 1e26014:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/1e260142290dad4de4a1177bb722eddd81c10623

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/17290

[changeset-bot]

⚠️ No Changeset found

Latest commit: 1e26014

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