Fix 23785: ICE with `-preview=in` when passing `enum` at CTFE

[Geod24]

[dlang-bot]

Thanks for your pull request, @Geod24!

Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	23785	regression	[REG ] `-preview=in` crash when passing `enum` value at CTFE

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 "stable + dmd#14999"

[Geod24]

@kinke and I discussed and there's a need for some more tests/work, as e.g. temporaries are now always destroyed even if not constructed.

[dkorpel]

Is this still an improvement on its own @Geod24 ?

[RazvanN7]

@Geod24 What's the status of this PR?

[kinke]

It needs work, as per the label.