feat: support report-sha256/report-sha384/report-sha512 CSP keywords

[willfarrell]

Adds support for the CSP hash-reporting keywords report-sha256, report-sha384, and report-sha512 (from the CSP Reporting spec (https://w3c.github.io/webappsec-csp/#reporting)) in the csp config.

Previously these keywords were not in the quoting allowlist, so SvelteKit emitted them unquoted (e.g. script-src report-sha256), producing an invalid header. They also weren't accepted by the Csp.ActionSource type.

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[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from 7cc4a31:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/7cc4a3194e814d97609c4297e09681ce3abfe3bf

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16867

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Latest commit: 7cc4a31

The changes in this PR will be included in the next version bump.

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@sveltejs/kit	Minor

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