[FEATURE] Support diff options (at least ignore whitespace) when showing "Update" tool diff for user approval

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

When claude code calls Update on a file in default mode (not "plan" or "auto accept edits") diffs are shown with whitespace changes and with unconfigurable context size

Proposed Solution

1. Add global configuration options for "ignore whitespace changes" (-b, --ignore-space-change in GNU diffutils diff and in git diff) and diff context size (-U<n>, --unified=<n>)
2. OR Allow changing these options interactively in the menu when the "Update" diff is shown to user

Alternative Solutions

_No response_

Priority

Medium - Would be very helpful

Feature Category

Interactive mode (TUI)

Use Case Example

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Additional Context

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