• List Role::Tiny (1.003000+) and Class::Method::Modifiers as
  RuntimeSuggests in dist.ini
  
• Skip role tests when Role::Tiny is missing or older than 1.003000
  (no is_role), so install is not blocked
  
• Move 'around' modifier test to its own file (t/role_modifiers.t)
  that skips when Class::Method::Modifiers is unavailable; Role::Tiny
  loads it lazily only for method modifiers (fixes #5)