Translate the ECMA-262 shorthand classes \d \w \s (and negations) into
their ASCII-only / ECMA-exact equivalents. std.regex interprets them as
Unicode-aware classes, but JSON Schema patterns use ECMA-262 semantics
where \d is exactly [0-9] and \w is [A-Za-z0-9_].
Translate the ECMA-262 shorthand classes \d \w \s (and negations) into their ASCII-only / ECMA-exact equivalents. std.regex interprets them as Unicode-aware classes, but JSON Schema patterns use ECMA-262 semantics where \d is exactly [0-9] and \w is [A-Za-z0-9_].