Input system does not update mouse position
`osi::mouse().position()->value()` is always `(0, 0)`.
I needed mouse position and had to do a workaround using SDL directly:
```cpp
float mouse_x = 0.0f;
float mouse_y = 0.0f;
SDL_GetMouseState(&mouse_x, &mouse_y);
```
Can be demonstrated by putting this code block into a `next_round` function of runner
```cpp
float mouse_x = 0.0f;
float mouse_y = 0.0f;
SDL_GetMouseState(&mouse_x, &mouse_y);
std::cout << "SDL mouse position: " << mouse_x << ", " << mouse_y << std::endl;
vec2 osi_mouse = osi::mouse().position()->value();
std::cout << "Input system mouse position: " << osi_mouse.x << ", " << osi_mouse.y << std::endl;
```
issue