The goal is to replicate the Search & Compare view in the Commit Details. This should be largely replicated, but need deeper review.

• make sure nothing is missing and fix bugs
• look at splitting the details panel so you can see both the details and the compare, would be nice to have the option to split panel horizontally or vertically

Verification steps:

• inverted diff direction
  • Open the Graph, enter compare mode comparing a feature branch against main
  • Verify the file list shows correct addition/deletion counts
  • Click the "Show All Diffs" button and confirm the multi-diff editor shows additions (green) for new code, not deletions (red)
  • Verify individual file diffs still open in the correct direction
  • Test with working tree changes (if applicable)