cleanup clang-tidy warnings

src/game/entities/Bullet.hpp

src/game/entities/Unit.cpp

src/game/entities/Unit.hpp

src/game/level/Level.cpp

src/game/level/Level.hpp

src/game/main.cpp

src/game/physics/PhysicsBody.cpp

src/game/physics/PhysicsEngine.cpp

src/game/physics/PhysicsEngine.hpp

src/game/ui/TileMarker.cpp

src/game/ui/context/ContextMenu.cpp

src/game/ui/context/ContextMenu.hpp

src/game/ui/context/RecruitingMenu.cpp

src/game/ui/context/RecruitingMenu.hpp

src/game/ui/menu/EndScreen.hpp

src/game/ui/menu/Menu.cpp

src/game/ui/menu/Menu.hpp

src/game/ui/menu/PauseMenu.cpp

src/game/ui/menu/PauseMenu.hpp

src/game/ui/modals/HelpMenu.cpp