Implement Tab Width

[thecoolwinter]

Description

This PR adds the tab stops implementation. It was previously thought to not function as expected but after comparing to other editors this is the correct implementation. Adding tab stops makes it so tabs stop at intervals along the document, so a tab will not act like a space but rather a break in the line until the next tab stop. Like so:

Raw:   |\t1\t2\t3
Visual:|----1---2---3

Raw:   |\tabc\t2\t3
Visual:|----abc-2---3

Related Issues

• Closes #80

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

Screen recording shows the width being updated in real time using a placeholder preference, as well as editing a line with tabs showing the tab stops go backwards only when needed.

https://user-images.githubusercontent.com/35942988/229870857-2cb2e40b-4c61-43ce-96c7-f79a8514cfbd.mov

[austincondiff]

Really awesome dude, nice work! I am surprised at how little was required to get this to work.