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/chat_panel.hpp

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "game/game_handler.hpp"
+#include "ui/ui_services.hpp"
 #include <vulkan/vulkan.h>
 #include <imgui.h>
 #include <string>
@@ -109,10 +110,16 @@ public:
     /** Reset all chat settings to defaults. */
     void restoreDefaults();
 
+    // Section 3.5: UIServices injection (Phase B singleton breaking)
+    void setServices(const UIServices& services) { services_ = services; }
+
     /** Replace $g/$G and $n/$N gender/name placeholders in quest/chat text. */
     std::string replaceGenderPlaceholders(const std::string& text, game::GameHandler& gameHandler);
 
 private:
+    // Section 3.5: Injected UI services (Phase B singleton breaking)
+    UIServices services_;
+
     // ---- Chat input state ----
     char chatInputBuffer_[512] = "";
     char whisperTargetBuffer_[256] = "";