Prevent full re-render on final KCL file deletion

[franknoirot]

@JordanNoone pointed out that there was a "crash" or something wrong when deleting the final KCL file in a project's top directory. This was a full refresh that felt more catastrophic in dark mode due to a separate issue fixed by #3794. But react-router-dom's navigation should prevent a full re-render of the page anyway, so I investigated and found the very smol cause.

Demo

Screenshare.-.2024-09-05.5_49_38.PM-compressed.mp4

[qa-wolf]

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Name	Status	Preview	Updated (UTC)
modeling-app	✅ Ready (Inspect)	Visit Preview	Sep 16, 2024 9:50pm

[jtran]

Nice.

[lf94]

Nice I thought the original did what the new does :D

[franknoirot]

This might have a real playwright failure https://github.com/KittyCAD/modeling-app/actions/runs/10729880216/job/29759277503?pr=3808#step:20:19343

[lf94]

I suspect the error is caused by a race in Windows (I just ran it again and 1 of 2 of the failed tests passed)

[franknoirot]

I'm going to look for /main.kcl somewhere in the codebase, I think something about this change generates a Unix-style path

Recording.2024-09-16.182853.mp4

[franknoirot]

It's so annoying and strange, I do not understand why things are so different from this one character change

[lf94]

Interesting, I am very wrong about my original idea 😆

Ok, this is good! I think this is way more tangible. I can help with this tomorrow 100%

[franknoirot]

Thank you! I do not get it, it's not the main.kcl think I was off. It's so weird to me that it's Windows-specific

[lf94]

I'll put this over the line; just leave it to me so you can get it off your mind