Add the show all option for Group.

tui_rsync/cli/groups/group_show.py

@@ -24,6 +24,7 @@ import typer
 
 from tui_rsync.models.models import Group, GroupSource
 from tui_rsync.cli.groups.group_prompt import GroupPrompt
+from tui_rsync.models.models import all_group_labels
 
 console = Console()
 group_show = typer.Typer()
@@ -51,3 +52,12 @@ def one(
 
     console.print(group.show_format())
 
+@group_show.command()
+def all():
+    """
+    [green b]Show[/] [yellow]all existing groups[/].
+    """
+    for label in all_group_labels().iterator():
+        group = Group.get_group(label.label)
+        console.print(group.show_format())
+