The test environment was creating cql_config with hardcoded default values that
were never updated when system.config was modified via CQL. This broke tests
that dynamically change configuration values (e.g., TWCS tests).
Fix by creating cql_config from db::config using sharded_parameter, which
ensures updateable_value fields track the actual db::config sources and reflect
changes made during test execution.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Signed-off-by: Pavel Emelyanov <xemul@scylladb.com>