Pitch

`apply_patch` and `edit_file` tool results currently render as raw unified-diff text. For multi-hunk changes the user has to mentally parse `--- `/`+++` markers and the `@@` hunk headers. Render it visually:

• Removed lines: STATUS_ERROR fg, dim
• Added lines: STATUS_OK fg, bold
• Hunk header: TEXT_DIM, italic, prefixed with file:line
• File header: ACCENT_SKY, separated visually

Already have the diff text — just need a parser pass at render time and palette-aware spans.

Acceptance

• apply_patch / edit_file results render with colored +/- lines.
• File and hunk headers visually distinct.
• Plain copy-paste of the cell still yields the original unified diff text (don't break clipboard).
• Standard verification gates pass.