modification and ascii/printable highlighting in hex/linear color highlight setting are mutually exclusive

They should be:
 
1. Both on by default (modified is hard to discover otherwise)
2. Independent so they can each be toggled

<img width="503" height="256" alt="Image" src="https://github.com/user-attachments/assets/2011a8e6-69fd-441b-ae92-930917c743c3" />