> ^, \A, $, \Z, \z are standard across many languages, based on PCRE syntax.

Uhm... No? ^$ have always meant beginning and end of string, not line, unless you turn on a flag. Not by default. You can check PCRE's documentation if you don't believe me. And then, there's Ruby:

  irb(main):005:0> "foo\nbar".match /o$/
  => #<MatchData "o">