feat(comment): comment on issues and pull requests the gh way

tea issue comment 12 --body "LGTM" failed with "unknown flag: --body"; the
comment had to be created with issue comment create. issue comment and
pr comment now take the issue or pull request and -b/-F/-e directly,
plus --edit-last and --delete-last for your last comment. The
subcommands stay, create is also add, and a misspelled subcommand
suggests the right one.

Comments are written in the configured editor or a multi-line
"Comment (markdown):" field, which edits start from the current text,
without a confirmation afterwards. The new comment's URL goes to stdout
with a ✓ line; deletes ask "Delete comment 81 on alice/x#1?". comment
list shows each comment under a "#79 alice • about 2 hours ago"
heading on a terminal and as key/value blocks when piped, and comment
JSON gains issue_number.

Signed-off-by: bircni <bircni@icloud.com>

internal/app/app.go

@@ -544,6 +544,9 @@ func commandOutputFields(cmd *cobra.Command) []string {
 	case "comment":
 		return jsonFields[services.Comment]()
 	case "issue":
+		if cmd.Name() == "comment" {
+			return jsonFields[services.Comment]()
+		}
 		return jsonFields[services.Issue]()
 	case "review":
 		if cmd.Name() == "request" || cmd.Name() == "cancel-request" {
@@ -563,6 +566,8 @@ func commandOutputFields(cmd *cobra.Command) []string {
 			return jsonFields[services.Review]()
 		case "clean":
 			return jsonFields[git.CleanResult]()
+		case "comment":
+			return jsonFields[services.Comment]()
 		}
 		return jsonFields[services.Pull]()
 	case "repo":