Fix NPC apparel fallback and reduce world-entry stutter

Hide NPC cloak/object-skin mesh when no cape texture resolves by using a transparent texture fallback, preventing skin-texture bleed on cloaks. Tighten NPC equipment region compositing by slot and add safe humanoid geoset selection to avoid robe-over-pants conflicts and odd pants texturing.

Reduce login/runtime hitching by deferring non-critical world-system initialization across frames, lowering per-frame transport doodad spawn budget, and demoting high-volume transport/MO_TRANSPORT diagnostics to debug. Gate M2 glow diagnostics behind WOWEE_M2_GLOW_DIAG and make zone music prewarm opt-in via WOWEE_PREWARM_ZONE_MUSIC.

include/rendering/character_renderer.hpp

@@ -216,6 +216,7 @@ public:
 
     /** Load a BLP texture from MPQ and return the GL texture ID (cached). */
     GLuint loadTexture(const std::string& path);
+    GLuint getTransparentTexture() const { return transparentTexture; }
 
     /** Replace a loaded model's texture at the given slot with a new GL texture. */
     void setModelTexture(uint32_t modelId, uint32_t textureSlot, GLuint textureId);
@@ -261,6 +262,7 @@ private:
     uint64_t textureCacheCounter_ = 0;
     size_t textureCacheBudgetBytes_ = 1024ull * 1024 * 1024;  // Default, overridden at init
     GLuint whiteTexture = 0;
+    GLuint transparentTexture = 0;
 
     std::unordered_map<uint32_t, M2ModelGPU> models;
     std::unordered_map<uint32_t, CharacterInstance> instances;

include/rendering/renderer.hpp

@@ -176,6 +176,8 @@ public:
     LightingManager* getLightingManager() { return lightingManager.get(); }
 
 private:
+    void runDeferredWorldInitStep(float deltaTime);
+
     core::Window* window = nullptr;
     std::unique_ptr<Camera> camera;
     std::unique_ptr<CameraController> cameraController;
@@ -259,6 +261,10 @@ private:
     bool inTavern_ = false;
     bool inBlacksmith_ = false;
     float musicSwitchCooldown_ = 0.0f;
+    bool deferredWorldInitEnabled_ = true;
+    bool deferredWorldInitPending_ = false;
+    uint8_t deferredWorldInitStage_ = 0;
+    float deferredWorldInitCooldown_ = 0.0f;
 
     // Third-person character state
     glm::vec3 characterPosition = glm::vec3(0.0f);