[fix] correct parent data type for layouts

[dummdidumm]

Was wrong if a layout referenced a named layout in the same folder
Fixes #6013

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[benmccann]

I believe there was an older issue related to sorting of routes somewhere. Probably not related to this, but thought I'd mention it in case you want to check if it closes that issue or you want to address both while working on the same section of code. I hear my kids waking up, so I don't have a chance to look for it at the moment

[dummdidumm]

Do you have an issue number? Can't find it.

[benmccann]

I can't find it either, so nevermind then 😄