Remove debug logging and add negative texture cache to fix lag spikes

Remove PPM composite dumps, MODEL1_BOUNDS vertex analysis, TEX_REGION
logging, FOUNTAIN_PARTICLES debug output, and verbose chat/warden gate
logging. Add negative cache for failed texture loads to prevent repeated
file I/O for missing textures like deathknighteyeglow.blp.

include/rendering/character_renderer.hpp

@@ -251,6 +251,7 @@ private:
     };
     std::unordered_map<std::string, TextureCacheEntry> textureCache;
     std::unordered_map<std::string, GLuint> compositeCache_;  // key → GPU texture for reuse
+    std::unordered_set<std::string> failedTextureCache_;  // negative cache for missing textures
     size_t textureCacheBytes_ = 0;
     uint64_t textureCacheCounter_ = 0;
     size_t textureCacheBudgetBytes_ = 1024ull * 1024 * 1024;  // Default, overridden at init