The long dash you refer to is actually called 'En Dash', a mulitbyte character. The short dash is an ascii hyphen which is what one would normally expect in a URL like that (maximum compatibility).
See:
https://unicode-table.com/en/2013/
https://unicode-table.com/en/002D/
As for why the board fucks it up, I can only guess, possibly something to do with whatever collation the board database uses to store text. The pic shows how one might get confused, the numbers you see are the UTF-16 decimal values for each character.