Allow texture load retries instead of permanently caching failures

Remove negative cache for transient load failures in M2, terrain, and
character renderers. Failed textures return white and will be retried
on next model/tile load when assets may have finished streaming.

include/rendering/character_renderer.hpp

@@ -264,7 +264,8 @@ private:
     std::unordered_map<VkTexture*, bool> textureHasAlphaByPtr_;
     std::unordered_map<VkTexture*, bool> textureColorKeyBlackByPtr_;
     std::unordered_map<std::string, VkTexture*> compositeCache_;  // key → texture for reuse
-    std::unordered_set<std::string> failedTextureCache_;  // negative cache for missing textures
+    std::unordered_set<std::string> failedTextureCache_;  // negative cache for budget exhaustion
+    std::unordered_set<std::string> loggedTextureLoadFails_;  // dedup warning logs
     size_t textureCacheBytes_ = 0;
     uint64_t textureCacheCounter_ = 0;
     size_t textureCacheBudgetBytes_ = 1024ull * 1024 * 1024;

src/rendering/character_renderer.cpp

@@ -526,17 +526,12 @@ VkTexture* CharacterRenderer::loadTexture(const std::string& path) {
         return whiteTexture_.get();
     }
 
-    // Check negative cache to avoid repeated file I/O for textures that don't exist
-    if (failedTextureCache_.count(key)) {
-        return whiteTexture_.get();
-    }
-
     auto blpImage = assetManager->loadTexture(key);
     if (!blpImage.isValid()) {
-        static constexpr size_t kMaxFailedTextureCache = 200000;
-        core::Logger::getInstance().warning("Failed to load texture: ", path);
-        if (failedTextureCache_.size() < kMaxFailedTextureCache) {
-            failedTextureCache_.insert(key);
+        // Return white fallback but don't cache the failure — allow retry
+        // on next character load in case the asset becomes available.
+        if (loggedTextureLoadFails_.insert(key).second) {
+            core::Logger::getInstance().warning("Failed to load texture: ", path);
         }
         return whiteTexture_.get();
     }

src/rendering/m2_renderer.cpp

@@ -3342,9 +3342,7 @@ VkTexture* M2Renderer::loadTexture(const std::string& path, uint32_t texFlags) {
         it->second.lastUse = ++textureCacheCounter_;
         return it->second.texture.get();
     }
-    if (failedTextureCache_.count(key)) {
-        return whiteTexture_.get();
-    }
+    // No negative cache check — allow retries for transiently missing textures
 
     auto containsToken = [](const std::string& haystack, const char* token) {
         return haystack.find(token) != std::string::npos;
@@ -3365,10 +3363,8 @@ VkTexture* M2Renderer::loadTexture(const std::string& path, uint32_t texFlags) {
     // Load BLP texture
     pipeline::BLPImage blp = assetManager->loadTexture(key);
     if (!blp.isValid()) {
-        static constexpr size_t kMaxFailedTextureCache = 200000;
-        if (failedTextureCache_.size() < kMaxFailedTextureCache) {
-            failedTextureCache_.insert(key);
-        }
+        // Return white fallback but don't cache the failure — MPQ reads can
+        // fail transiently during streaming; allow retry on next model load.
         if (loggedTextureLoadFails_.insert(key).second) {
             LOG_WARNING("M2: Failed to load texture: ", path);
         }

src/rendering/terrain_renderer.cpp

@@ -442,16 +442,10 @@ VkTexture* TerrainRenderer::loadTexture(const std::string& path) {
         it->second.lastUse = ++textureCacheCounter_;
         return it->second.texture.get();
     }
-    if (failedTextureCache_.count(key)) {
-        return whiteTexture.get();
-    }
-
     pipeline::BLPImage blp = assetManager->loadTexture(key);
     if (!blp.isValid()) {
-        static constexpr size_t kMaxFailedTextureCache = 200000;
-        if (failedTextureCache_.size() < kMaxFailedTextureCache) {
-            failedTextureCache_.insert(key);
-        }
+        // Return white fallback but don't cache the failure — allow retry
+        // on next tile load in case the asset becomes available.
         if (loggedTextureLoadFails_.insert(key).second) {
             LOG_WARNING("Failed to load texture: ", path);
         }