doc: update layout and widget interface documentation

src/layout.zig

@@ -1,16 +1,13 @@
-//! Dynamic dispatch for layout implementations.
-//! Each layout should at least implement these functions:
-//! - handle(this: *@This(), event: Event) anyerror!*std.ArrayList(Event) {}
-//! - render(this: *@This(), renderer: *Renderer) anyerror!void {}
-//! - deinit(this: *@This()) void {}
+//! Dynamic dispatch for layout implementations. Each `Layout` has to implement
+//! the `Layout.Interface`.
 //!
 //! Create a `Layout` using `createFrom(object: anytype)` and use them through
-//! the defined interface. The layout will take care of calling the correct
-//! implementation of the corresponding underlying type.
+//! the defined `Layout.Interface`. The layout will take care of calling the
+//! correct implementation of the corresponding underlying type.
 //!
 //! Each `Layout` is responsible for clearing the allocated memory of the used
-//! widgets when deallocated. This means that `deinit()` will also deallocate
-//! every used widget too.
+//! `Element`s (union of `Layout` or `Widget`) when deallocated. This means
+//! that `deinit()` will also deallocate every used `Element` too.
 //!
 //! When `Layout.render` is called the provided `Renderer` type is expected
 //! which handles how contents are rendered for a given layout.
@@ -95,7 +92,6 @@ pub fn Layout(comptime Event: type, comptime Renderer: type) type {
     };
     // test widget implementation satisfies the interface
     comptime Type.Interface.satisfiedBy(Type);
-    // TODO: there is a dependency loop (due to the necessary `Layout` type for the `Element`)
     comptime Type.Interface.satisfiedBy(Type.HStack);
     comptime Type.Interface.satisfiedBy(Type.VStack);
     comptime Type.Interface.satisfiedBy(Type.Padding);