[API] Add diff hunks to the list of affected files in a commit

[GamerGirlandCo]

Feature Description

It would be nice if the CommitAffectedFile model included a diff of what changed in that file for a specific commit. Happy to open a pull request to implement this! :)

Screenshots

No response

[wxiaoguang]

It should be optional, otherwise it slows down the API when the caller doesn't need it.