This aims to make future refactoring easier. The arguments are removed where possible, but kept and marked with C++17's [[maybe_unused]] where they could not be removed (e.g. when they are used as a callback, rather than called directly).
I've skipped the rides/<category>/* and peep/* source files, because the rides source files are mostly generated and have a ton of unused variables, and the peep source files are being refactored.
I've also skipped most of window/* source files, because most of the functions are used as callbacks and will be bulk-renamed at some point.
`typedef struct/union/enum name { ... } name_again;` is not needed whe compiling C++, moving the name at the back to be in front of the object and removing `typedef` makes it usable the very same way.
This also replaces typedefs with the using keyword. They have better readability, especially for function pointer types, and would allow more flexibility when used with templates.
