Replace the raw single-blob diff dump (Monaco, language=diff) and the plain
<pre> file diffs in chat with @git-diff-view/react:
- Parse the unified git diff into structured per-file entries (status,
+/- counts, binary detection) via parseDiffFiles()
- Workspace Diff tab: collapsible per-file cards with status badges, line
counts, syntax highlighting, and a Unified/Split toggle
- Agent chat: render each change's diff highlighted instead of plain text
- Theme follows next-themes resolvedTheme (light/dark)
Gabriel Brown