Fix Padding Issue, Assertion Failure On Width Update

[thecoolwinter]

Description

• Considers the edge insets when calculating the 'max width' in the layout manager. Fixes a bug where trailing text is clipped when not wrapping lines because the width of the text view is not large enough.
• Fixes a potential assertion failure when notifying of a width update from the layout manager. Moves the delegate call to outside the protected area so that anything that may need to respond to a width adjustment can cause a layout pass without causing an invalid state.

Related Issues

• Adjust Gutter Background, Add Trailing Padding CodeEditSourceEditor#272

Checklist

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

Screenshots

N/A