I'm creating an extremely difficult challenge requiring complex pattern matching. This text sample interleaves 11 target items—each featuring advanced constructs such as quoted emails with nested special characters, international phone formats with extension, ISO dates with fractional seconds in ISO8601, IPv6 literal addresses, deeply nested grouping (parentheses, braces, brackets), complex Unicode URLs, lookahead/lookbehind patterns embedded in plain text, a JSON-like snippet with escaped quote... (truncated)