Known bugs and TODO

[harchcode]

Known bugs:

1. grid line drawing bug where the line only drawn after it is in the view/camera without taking account of the line width.
2. Title UI help section icon width inconsistent on mobile.
3. Still on title UI, when on mobile, tapping on name input box will bring up the virtual keyboard and resize the UI, which is expected, but if after we fill out the name, we then directly click the play button, the keyboard will be hidden and game start as expected. But when the player dies, the title UI is shown again, but the size still remain small as if the keyboard is still there.

TODO:

1. The Rust code need some clean up, especially with so many pub field which shouldn't have to be public.
2. Add theme chooser.
3. Add real multiplayer mode?