feat: Dynamic command loader, default command with module registry

Commands/RootCommand.cs

@@ -0,0 +1,38 @@
+using Automancer.Common;
+using Spectre.Console;
+using Spectre.Console.Cli;
+using System.Diagnostics.CodeAnalysis;
+
+namespace Automancer.Commands;
+
+public class RootCommand : Spectre.Console.Cli.Command
+{
+    private readonly CommandRegistry _registry;
+
+    public RootCommand(CommandRegistry registry)
+    {
+        _registry = registry;
+    }
+    public override int Execute([NotNull] CommandContext context)
+    {
+        AnsiConsole.Write(
+            new FigletText("AUTOMANCER")
+                .Centered()
+                .Color(Color.Cyan1));
+
+        AnsiConsole.MarkupLine("[bold]Automancer[/] is a modular CLI automation tool. It is designed to be extensible and easy to use.");
+        AnsiConsole.MarkupLine("Use [green]--help[/] or [green]<command> --help[/] to get started.");
+
+        var table = new Table().Border(TableBorder.Rounded);
+        table.AddColumn("[bold yellow]Module[/]");
+        table.AddColumn("[bold yellow]Description[/]");
+
+        foreach (var cmd in _registry.Commands.OrderBy(c => c.Path))
+        {
+            table.AddRow($"[green]{cmd.Path}[/]", cmd.Description ?? "[dim]n/a[/]");
+        }
+
+        AnsiConsole.Write(table);   
+        return 0;
+    }
+}