[FEATURE] configurable diff tool eg delta that displays function names and has syntax highlighting in term

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

Similarly to git I think it would be really cool if one could configure a diff tool that is being used by claude-code.
Colorized syntax and function name before every major chunk and more...

Proposed Solution

Config setting to allow to set diff tool and/or a pager.
Ideally I'd like to use things like delta: https://github.com/dandavison/delta

Alternative Solutions

Better syntax highlighting in diffs and class/function name before every major chunk.

Priority

Medium - Would be very helpful

Feature Category

Developer tools/SDK

Use Case Example

Any code change that I review presents me a diff but
but the format is different from what I used to from git diff and modern diff tools...

Additional Context

Please see tools like delta