Add the remaining Patch actions to the CLI interface. These include:

• React to a revision
• Edit a comment
• React to a comment
• Redact a comment

The react subcommand is added in a straight-forward manner.

The comment commands are slightly less straight-forward. In order to keep to one layer of subcommands, these variants are done through the rad patch comment subcommand. They are accessed via options: --edit, --react, and --redact, respectively. Each of these options takes the CommentId for which the action is affecting. The message, react (introduced for rad patch react), and undo variables repurposed for this subset of actions.

Rebase.