Vanilla/Turtle WoW support: M2 loading, bone parsing, textures, auth

- Vanilla M2 bone struct (108 bytes) with 28-byte animation tracks
- Version-aware bone parsing (vanilla vs WotLK format detection)
- Fix CharSections.dbc field layout for vanilla (variation/color at 4-5)
- Remove broken CharSections.csv files (all fields marked as strings)
- Expansion data reload on profile switch (DBC cache clear, layout reload)
- Vanilla packet encryption (VanillaCrypt XOR-based header crypt)
- Extended character preview geoset range (0-99) for vanilla models
- DBC cache clear support in AssetManager

src/pipeline/asset_manager.cpp

@@ -396,6 +396,12 @@ std::vector<uint8_t> AssetManager::readFileOptional(const std::string& path) con
     return readFile(path);
 }
 
+void AssetManager::clearDBCCache() {
+    std::lock_guard<std::mutex> lock(cacheMutex);
+    dbcCache.clear();
+    LOG_INFO("Cleared DBC cache");
+}
+
 void AssetManager::clearCache() {
     std::lock_guard<std::mutex> lock(cacheMutex);
     dbcCache.clear();