feat: add editor resizable bar

[Deanly]

Pull request again because of the issue of not using the feature branch.

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Thanks to you making this project, my work has become more enjoyable.

This feature was what I needed. And developed and used. I think it's worth sharing for now.

from #5253

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test

rate per tick : 10%

https://user-images.githubusercontent.com/22494876/168629768-eb525cf8-86d6-4ec7-9547-25e8d4775224.mp4

rate per tick : 2%

https://user-images.githubusercontent.com/22494876/168629787-0ccf335a-b77b-4021-8fe6-623eab35025b.mp4