Fix ICE when combining --optimize with --no-optimize-yul

[heathdutton]

Fixes #16306

Using --optimize --no-optimize-yul caused an internal compiler error in createMetadata() because optimizeStackAllocation remained true (from OptimiserSettings::standard()) while runYulOptimiser was set to false.

This PR sets optimizeStackAllocation to match runYulOptimiser, ensuring consistency.

[github-actions]

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