| GET | .../preview/diff/files | Every changed file with its status and line counts, plus totals. No content diff, so this is cheap. |
| GET | .../preview/diff/patch?cursor= | One page of file patches. |
| GET | .../preview/diff/patch?path=&hunkOffset=&hunkEnd= | Specific hunks of one file. |
| GET | .../preview/diff/comments | Every diff comment on the session. |
| POST | .../preview/diff/comments | Add one. Body { filePath, side, startLineNumber, endLineNumber, body, lineSnapshot }, side is old or new. |
| PATCH | .../preview/diff/comments/{commentId} | { body } to edit, author only. { resolved } to resolve, anyone with access. |
| DELETE | .../preview/diff/comments/{commentId} | Author only. |