Make KRR allocate @safe

[denisa1208]

My PR revives the original PR (https://github.com/dlang/phobos/actions/runs/12297111982/job/34317628480?pr=10585)

[dlang-bot]

Thanks for your pull request and interest in making D better, @denisa1208! We are looking forward to reviewing it, and you should be hearing from a maintainer soon.
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Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + phobos#10585"