docs(create): document --no-download-check option

[manuel3108]

The sv create command supports --no-download-check, but its command documentation omitted the option even though the corresponding sv add documentation includes it. Document the flag and its security caveat, and add an sv patch changeset.

Closes #1309

Validation: pnpm lint

[pkg-svelte-dev]

Install the latest version of sv from 901b9a1:

pnx https://pkg.svelte.dev/sv/c/901b9a1eb88ec901d43d73e1df6663a4d5234526 create

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/cli/pr/1318

[changeset-bot]

⚠️ No Changeset found

Latest commit: 901b9a1

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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[svelte-docs-bot]

Preview: https://svelte-dev-git-preview-cli-1318-svelte.vercel.app/

[sacrosanctic]

Do we need to add the docs to the CLI itself?