A slash command definition with name, description, and optional aliases.
Examples
iex> %ExRatatui.Widgets.SlashCommands.Command{name: "help", description: "Show help"}
%ExRatatui.Widgets.SlashCommands.Command{name: "help", description: "Show help", aliases: []}
iex> %ExRatatui.Widgets.SlashCommands.Command{name: "quit", aliases: ["exit", "q"]}
%ExRatatui.Widgets.SlashCommands.Command{name: "quit", description: "", aliases: ["exit", "q"]}