Inserts a new record associating an individual user with a security-group into the MENU_SECURITY_USER table. The primary key is generated inline via MENU_SECURITY_USER_SEQ.NEXTVAL in the SQL (no separate sequence query).
Note: Statements marked with * were inferred from code structure, naming conventions, or contextual evidence where direct confirmation was not available in source artifacts. Statements marked with ** could not be confirmed; treat as unknown until verified.