ui: add main menu scene and interactive button widget

- Implement MainMenuScene with a "Start Game" button that pushes the WorldScene.
- Extend Button class with background/foreground, hover detection, and size queries.
- Add virtual width/height and event handlers to Widget base class.
- Update WorldUIManager to propagate mouse move events.
- Adjust Window mouse mode based on game running state.

src/ui/world_ui_manager.cpp

@@ -22,7 +22,12 @@ void WorldUIManager::init() {
         .set_scale(3.0f);
     m_widgets.try_emplace("crosshair", std::move(crosshair));
 }
-void WorldUIManager::update(float) {}
+void WorldUIManager::update(float dt) {
+
+    for (auto& w : m_widgets) {
+        w.second->update(dt);
+    }
+}
 void WorldUIManager::render(Renderer& renderer) {
     renderer.begin_render_ui();
 
@@ -36,7 +41,12 @@ void WorldUIManager::render(Renderer& renderer) {
 }
 bool WorldUIManager::handle_event(const Event& e) {
     return std::visit(
-        Overloaded{[](const MouseMoveEvent&) { return false; },
+        Overloaded{[this](const MouseMoveEvent& e) {
+                       if (handle_mouse_move_event(e)) {
+                           return true;
+                       }
+                       return false;
+                   },
                    [this](const MouseButtonEvent& e) {
                        if (handle_mouse_button_event(e)) {
                            return true;
@@ -65,8 +75,20 @@ bool WorldUIManager::handle_event(const Event& e) {
         },
         e);
 }
-
-bool WorldUIManager::handle_mouse_button_event(const MouseButtonEvent&) {
+bool WorldUIManager::handle_mouse_move_event(const MouseMoveEvent& e) {
+    for (auto& w : m_widgets) {
+        if (w.second->handle_mouse_move_event(e)) {
+            return true;
+        }
+    }
+    return false;
+}
+bool WorldUIManager::handle_mouse_button_event(const MouseButtonEvent& e) {
+    for (auto& w : m_widgets) {
+        if (w.second->handle_mouse_button_event(e)) {
+            return true;
+        }
+    }
     return false;
 }
 bool WorldUIManager::handle_window_resize_event(const WindowResizeEvent& e) {
@@ -78,11 +100,29 @@ bool WorldUIManager::handle_window_resize_event(const WindowResizeEvent& e) {
                                     e.height / 2 + crosshair->height() / 2);
         }
     }
+    for (auto& w : m_widgets) {
+        if (w.second->handle_window_resize_event(e)) {
+            return true;
+        }
+    }
     return false;
 }
-bool WorldUIManager::handle_mouse_wheel_event(const MouseWheelEvent&) {
+bool WorldUIManager::handle_mouse_wheel_event(const MouseWheelEvent& e) {
+    for (auto& w : m_widgets) {
+        if (w.second->handle_mouse_wheel_event(e)) {
+            return true;
+        }
+    }
+    return false;
+}
+bool WorldUIManager::handle_key_event(const KeyEvent& e) {
+    for (auto& w : m_widgets) {
+        if (w.second->handle_key_event(e)) {
+            return true;
+        }
+    }
+
     return false;
 }
-bool WorldUIManager::handle_key_event(const KeyEvent&) { return false; }
 
 } // namespace Cubed