Add `jqtxt --object` to require a single object
Add `jqtxt --object` to require a single object

Some inputs appear to be valid JSON or JSONL, but aren't really what's
needed for a command that requires JSON. (e.g., `seq 10` is valid JSONL)

benizi/dotfiles,benizi/dotfiles,benizi/dotfiles,benizi/dotfiles,benizi/dotfiles,benizi/dotfiles,benizi/dotfiles,benizi/dotfiles