cli: add system migrations command skeleton and tests

src/Cli/__Tests/StellaOps.Cli.Tests/Commands/SystemCommandBuilderTests.cs

@@ -0,0 +1,31 @@
+using System.CommandLine;
+using StellaOps.Cli.Commands;
+using StellaOps.Cli.Services;
+using Xunit;
+
+namespace StellaOps.Cli.Tests.Commands;
+
+public class SystemCommandBuilderTests
+{
+    [Fact]
+    public void BuildSystemCommand_AddsMigrationsSubcommands()
+    {
+        var system = SystemCommandBuilder.BuildSystemCommand();
+        Assert.NotNull(system);
+        Assert.Equal("system", system.Name);
+        Assert.Contains(system.Subcommands, c => c.Name == "migrations-run");
+        Assert.Contains(system.Subcommands, c => c.Name == "migrations-status");
+        Assert.Contains(system.Subcommands, c => c.Name == "migrations-verify");
+    }
+
+    [Fact]
+    public void ModuleNames_Contains_All_Modules()
+    {
+        Assert.Contains("Authority", MigrationModuleRegistry.ModuleNames);
+        Assert.Contains("Scheduler", MigrationModuleRegistry.ModuleNames);
+        Assert.Contains("Concelier", MigrationModuleRegistry.ModuleNames);
+        Assert.Contains("Policy", MigrationModuleRegistry.ModuleNames);
+        Assert.Contains("Notify", MigrationModuleRegistry.ModuleNames);
+        Assert.Contains("Excititor", MigrationModuleRegistry.ModuleNames);
+    }
+}