static ROLES_PATTERN: LazyLock<Regex>Expand description
Allowlist of characters permitted in the value spliced into the
SHOW GRANTS ... USING <roles> query. The value originates from the
upstream MySQL server’s CURRENT_ROLE() and must be conservatively
validated to prevent SQL injection. Comma-separated role specs of the
form `role`@`host` or 'role'@'host' use only this character set.