fix: address PR #31 and #32 review findings

- Dockerfile: fix LLVM apt repo codename (jammy → noble) for ubuntu:24.04
- build-linux.sh: add missing mkdir -p /wowee-build-src before tar extraction
- Dockerfile: remove dead ENV OSXCROSS_VERSION=1.5 and its unset
- CMakeLists: scope -undefined dynamic_lookup to wowee target only
- GameServices: remove redundant game:: qualifier inside namespace game
- application.cpp: zero out gameServices_ after gameHandler reset in shutdown

src/core/application.cpp

@@ -921,6 +921,7 @@ void Application::shutdown() {
     world.reset();
     LOG_WARNING("Resetting gameHandler...");
     gameHandler.reset();
+    gameServices_ = {};
     LOG_WARNING("Resetting authHandler...");
     authHandler.reset();
     LOG_WARNING("Resetting assetManager...");