git ssb

Line comment

{
  "type": "line-comment",
  "text": string,
  "mentions": Links,
  "repo": MsgId,
  "updateId": MsgId,
  "commitId": string,
  "filePath": string,
  "line": number,
}

repo: id of git-repo
text: text of the comment mentions: mentions links associated with the text, as done with post messages updateId: id of a git-update message that pushed the git commit, git trees, and git blobs needed to render the diff. commitId: commit that the comment is on filePath: path to the file that the comment is on line: line number of the file that the comment is on

A reply to a line comment should be a message of type post with root
property set to the id of the line-comment message. branch property should follow the semantics of branch used in other post message threads.