Pending change review for DeepSeek Harness

Key features

• Diff viewsyntax-highlighted whole-file diff ⑤ with +/− counts, an overview ruler ④ on the scrollbar showing where changes sit, and an in-file search (Ctrl+F).
• Only tracked mutations (edit, write, and str_replace_editor editor calls) are recorded automatically.
• Rows are virtualized, so huge files stay smooth.
• Block navigation & decisionsjump between change blocks with Ctrl+↑/↓ (or the previous/next buttons) — the focused block flashes.
• Hover a block to Keep or Revert just that block from a small actions frame ③ that also shows its position (e.g.