Added sidebar expand hover delay

[jamaan-s]

Proposed changes

Added a delay to sidebar expand when hover over it,
also added the ability to change the "ms" for the delay in the UI settings.

This is more for my own open issue here: #1147

it was easy to add, so i did it.

Types of changes

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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

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