chore(application): extract appearance controller and unify UI flow

- Refactor UI application architecture: extracted appearance controller into ui_services.hpp + implementation updates
- Update UI components and managers to use new service layer:
  - `action_bar_panel`, `auth_screen`, `character_screen`, `chat_panel`, `combat_ui`, `dialog_manager`, `game_screen`, `settings_panel`, `social_panel`, `toast_manager`, `ui_manager`, `window_manager`
- Adjust core application entrypoints:
  - application.cpp
- Update component implementations for new controller flow:
  - action_bar_panel.cpp, `chat_panel.cpp`, `combat_ui.cpp`, `dialog_manager.cpp`, `game_screen.cpp`, `settings_panel.cpp`, `social_panel.cpp`, `toast_manager.cpp`, `window_manager.cpp`

These staged changes implement a major architectural refactor for UI/appearance controller separation

include/ui/dialog_manager.hpp

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "ui/ui_services.hpp"
 #include <imgui.h>
 #include <string>
 #include <cstdint>
@@ -34,7 +35,12 @@ public:
     /// called in render() after reclaim corpse button
     void renderLateDialogs(game::GameHandler& gameHandler);
 
+    // Section 3.5: UIServices injection (Phase B singleton breaking)
+    void setServices(const UIServices& services) { services_ = services; }
+
 private:
+    // Section 3.5: Injected UI services
+    UIServices services_;
     // Common ImGui window flags for popup dialogs
     static constexpr ImGuiWindowFlags kDialogFlags =
         ImGuiWindowFlags_NoCollapse | ImGuiWindowFlags_NoResize;