Implement remaining CStateManager stubs

Runtime/World/CDestroyableRock.hpp

@@ -0,0 +1,20 @@
+#ifndef __URDE_CDESTROYABLEROCK_HPP__
+#define __URDE_CDESTROYABLEROCK_HPP__
+
+#include "CAi.hpp"
+
+namespace urde
+{
+
+class CDestroyableRock : public CAi
+{
+public:
+    CDestroyableRock(TUniqueId id, bool active, const std::string& name, const CEntityInfo& info,
+                     const zeus::CTransform& xf, CModelData&& modelData, float mass, const CHealthInfo& health,
+                     const CDamageVulnerability& vulnerability, const CMaterialList& matList, ResId fsm,
+                     const CActorParameters& actParams, const CModelData& modelData2);
+};
+
+}
+
+#endif // __URDE_CDESTROYABLEROCK_HPP__