Function libsql_dir_for 

pub fn libsql_dir_for(config: &ServerConfig, data_dir: &Path) -> Option<PathBuf>

The libsql data directory for a node config’s handlers.bindings.sql (single-node), mirroring handlers::build_sql_backends: handlers.bindings.sql.dir, else {data_dir}/handlers-sql. Only meaningful for a LOCAL (non-url) libsql binding — a remote sqld has no local directory.