Make Ctrl-Z Ignorance Configurable in ClickHouse Client

Why it matters

This feature allows users to decide whether the clickhouse-client should ignore the Ctrl-Z key combination, which by default suspends the client process. It helps prevent accidental suspensions when users use the client in interactive shells and improves the user experience by providing flexibility in signal handling.

How to use it

Users can enable or disable ignoring Ctrl-Z in clickhouse-client by setting the ignore_shell_suspend option. This can be done via the client configuration file or by passing the option at runtime.