chore(application): extract entity spawner + composer, apply app and UI updates

- add include/core/appearance_composer.hpp + src/core/appearance_composer.cpp
- update include/core/application.hpp + src/core/application.cpp
- update src/ui/game_screen.cpp
- adjust CMakeLists.txt and README.md for new composer module

include/core/appearance_composer.hpp

@@ -0,0 +1,101 @@
+#pragma once
+
+#include "game/character.hpp"
+#include <string>
+#include <vector>
+#include <unordered_set>
+#include <cstdint>
+
+namespace wowee {
+
+namespace rendering { class Renderer; }
+namespace pipeline { class AssetManager; class DBCLayout; struct M2Model; }
+namespace game { class GameHandler; }
+
+namespace core {
+
+class EntitySpawner;
+
+// Default (bare) geoset IDs per equipment group.
+// Each group's base is groupNumber * 100; variant 01 is typically bare/default.
+constexpr uint16_t kGeosetDefaultConnector = 101;   // Group  1: default hair connector
+constexpr uint16_t kGeosetBareForearms     = 401;   // Group  4: no gloves
+constexpr uint16_t kGeosetBareShins        = 503;   // Group  5: no boots
+constexpr uint16_t kGeosetDefaultEars      = 702;   // Group  7: ears
+constexpr uint16_t kGeosetBareSleeves      = 801;   // Group  8: no chest armor sleeves
+constexpr uint16_t kGeosetDefaultKneepads  = 902;   // Group  9: kneepads
+constexpr uint16_t kGeosetDefaultTabard    = 1201;  // Group 12: tabard base
+constexpr uint16_t kGeosetBarePants        = 1301;  // Group 13: no leggings
+constexpr uint16_t kGeosetNoCape           = 1501;  // Group 15: no cape
+constexpr uint16_t kGeosetWithCape         = 1502;  // Group 15: with cape
+constexpr uint16_t kGeosetBareFeet         = 2002;  // Group 20: bare feet
+
+/// Resolved texture paths from CharSections.dbc for player character compositing.
+struct PlayerTextureInfo {
+    std::string bodySkinPath;
+    std::string faceLowerPath;
+    std::string faceUpperPath;
+    std::string hairTexturePath;
+    std::vector<std::string> underwearPaths;
+};
+
+/// Handles player character visual appearance: skin compositing, geoset selection,
+/// texture path lookups, and equipment weapon rendering.
+class AppearanceComposer {
+public:
+    AppearanceComposer(rendering::Renderer* renderer,
+                       pipeline::AssetManager* assetManager,
+                       game::GameHandler* gameHandler,
+                       pipeline::DBCLayout* dbcLayout,
+                       EntitySpawner* entitySpawner);
+
+    // Player model path resolution
+    std::string getPlayerModelPath(game::Race race, game::Gender gender) const;
+
+    // Phase 1: Resolve texture paths from CharSections.dbc and fill model texture slots.
+    // Call BEFORE charRenderer->loadModel().
+    PlayerTextureInfo resolvePlayerTextures(pipeline::M2Model& model,
+                                           game::Race race, game::Gender gender,
+                                           uint32_t appearanceBytes);
+
+    // Phase 2: Apply composited textures to loaded model instance.
+    // Call AFTER charRenderer->loadModel(). Saves skin state for re-compositing.
+    void compositePlayerSkin(uint32_t modelSlotId, const PlayerTextureInfo& texInfo);
+
+    // Build default active geosets for player character
+    std::unordered_set<uint16_t> buildDefaultPlayerGeosets(uint8_t hairStyleId, uint8_t facialId);
+
+    // Equipment weapon loading (reads inventory, attaches weapon M2 models)
+    void loadEquippedWeapons();
+
+    // Weapon sheathe state
+    void setWeaponsSheathed(bool sheathed) { weaponsSheathed_ = sheathed; }
+    bool isWeaponsSheathed() const { return weaponsSheathed_; }
+    void toggleWeaponsSheathed() { weaponsSheathed_ = !weaponsSheathed_; }
+
+    // Saved skin state accessors (used by game_screen.cpp for equipment re-compositing)
+    const std::string& getBodySkinPath() const { return bodySkinPath_; }
+    const std::vector<std::string>& getUnderwearPaths() const { return underwearPaths_; }
+    uint32_t getSkinTextureSlotIndex() const { return skinTextureSlotIndex_; }
+    uint32_t getCloakTextureSlotIndex() const { return cloakTextureSlotIndex_; }
+
+private:
+    bool loadWeaponM2(const std::string& m2Path, pipeline::M2Model& outModel);
+
+    rendering::Renderer* renderer_;
+    pipeline::AssetManager* assetManager_;
+    game::GameHandler* gameHandler_;
+    pipeline::DBCLayout* dbcLayout_;
+    EntitySpawner* entitySpawner_;
+
+    // Saved at spawn for skin re-compositing on equipment changes
+    std::string bodySkinPath_;
+    std::vector<std::string> underwearPaths_;
+    uint32_t skinTextureSlotIndex_ = 0;
+    uint32_t cloakTextureSlotIndex_ = 0;
+
+    bool weaponsSheathed_ = false;
+};
+
+} // namespace core
+} // namespace wowee