* fix(gateguard): detect destructive SQL passed quoted to SQL clients
Quoted SQL like psql -c "drop table users" was stripped before the DESTRUCTIVE_SQL_DD regex ran, making it unreachable. Check dequoted tokens for known SQL clients (psql, mysql, sqlite3, ...) so real invocations are gated while git commit -m / echo mentions stay allowed. Fixesaffaan-m/ECC#3024.
* fix(gateguard): unwrap sudo/env flags and ignore SQL string literals
Address review: sudo -u/env VAR= wrappers now resolve to the real SQL client; SQL single/double/dollar-quoted literals are stripped before the destructive regex so SELECT 'drop table' stays allowed. Adds deny/allow regression tests for quoted SQL, wrappers, literals, and non-SQL clients.
* test(gateguard): cover env PGPASSWORD wrapper variant
* fix(gateguard): close wrapper sh-c, env dir, tagged literal gaps
Review 5189686662: recurse sh -c from unwrapped wrapper index (sudo/doas/env + sh -c now denied); consume env -C/--chdir separate values; strip tagged dollar-quoted literals ($tag$...\baseline). Tests: 200 passed.