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/ui/auth_screen.cpp

@@ -96,6 +96,7 @@ void AuthScreen::selectServerProfile(int index) {
             for (int i = 0; i < static_cast<int>(profiles.size()); ++i) {
                 if (profiles[i].id == s.expansionId) { expansionIndex = i; break; }
             }
+            core::Application::getInstance().reloadExpansionData();
         }
     }
 }
@@ -311,6 +312,7 @@ void AuthScreen::render(auth::AuthHandler& authHandler) {
                 if (ImGui::Selectable(label.c_str(), selected)) {
                     expansionIndex = i;
                     registry->setActive(profiles[i].id);
+                    core::Application::getInstance().reloadExpansionData();
                 }
                 if (selected) ImGui::SetItemDefaultFocus();
             }