Add RegisterAll and RegisterAllFrom methods

They are helper methods that register
multiple modules at once, the latter
registering all modules from an Assembly.

src/gaemstone/ECS/Universe+Modules.cs

@@ -17,6 +17,15 @@ public class ModuleManager
 	internal ModuleInfo? Lookup(Entity entity)
 		=> _modules.GetValueOrDefault(entity);
 
+	public void RegisterAllFrom(System.Reflection.Assembly assembly)
+		=> RegisterAll(assembly.GetTypes());
+	public void RegisterAll(IEnumerable<Type> types)
+	{
+		foreach (var type in types)
+			if (type.Has<ModuleAttribute>())
+				Register(type);
+	}
+
 	public EntityRef Register<T>()
 		where T : class => Register(typeof(T));
 	public EntityRef Register(Type type)

src/gaemstone/ECS/Universe.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using static flecs_hub.flecs;
 
 namespace gaemstone.ECS;
@@ -15,17 +16,20 @@ public unsafe partial class Universe
 
 	public Universe(params string[] args)
 	{
-		Handle = ecs_init_w_args(args.Length, null);
-
+		Handle  = ecs_init_w_args(args.Length, null);
 		Modules = new(this);
-		Modules.Register(typeof(Flecs.Core));
-		Modules.Register(typeof(Flecs.Pipeline));
-		Modules.Register(typeof(Flecs.ObserverEvent));
-		Modules.Register(typeof(Flecs.SystemPhase));
+
+		// Register built-in (static) modules, which
+		// are defined in the "gaemstone.Flecs" namespace.
+		Modules.RegisterAll(GetType().Assembly.GetTypes()
+			.Where(t => t.IsAbstract && t.IsSealed));
 
 		ChildOf = LookupOrThrow<Flecs.Core.ChildOf>();
 
-		New("Game").Symbol("Game").Build().CreateLookup<Game>().Add<Game>();
+		// Create "Game" singleton entity, which
+		// stores global state, configuration, ...
+		New("Game").Symbol("Game").Build()
+			.CreateLookup<Game>().Add<Game>();
 	}
 
 	public EntityBuilder New(EntityPath? path = null)