Adjust Gutter Background, Add Trailing Padding

Description

Updates the gutter to consider an inset for where to draw it's background.
Adds some padding to the trailing edge when line wrap is disabled. This is not an opened issue, but while I was adjusting padding might as well.

Related Issues

closes #271

Checklist

[x] I read and understood the contributing guide as well as the code of conduct
[x] The issues this PR addresses are related to each other
[x] My changes generate no new warnings
[x] My code builds and runs on my machine
[x] My changes are all related to the related issue above
[x] I documented my code

Screenshots

New leading gutter padding, includes some spacing between where the gutter starts to overlap the text and where the gutter is spaced to.

https://github.com/user-attachments/assets/35688a7f-d157-428d-9eac-8cfb35c62a1e

Xcode Comparison

Xcode: ![Screenshot 2024-11-07 at 9 40 22 PM](https://github.com/user-attachments/assets/5c9ffbbe-53f1-4834-b7cc-5256905dc37f) CodeEdit: ![Screenshot 2024-11-07 at 9 39 34 PM](https://github.com/user-attachments/assets/d90e7dbf-1311-48e6-b6d1-08dbf3531fe9)

Added some padding to the trailing edge when line wrap is disabled:

Screenshot 2024-11-07 at 10 18 00 PM

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