Disable Network Access for Default User in Docker Image and Enhance clickhouse-server Functionality

Disable network access for user default in the docker image. #75259 (Mikhail f. Shiryaev). Make all clickhouse-server related actions a function, and execute them only when launching the default binary in entrypoint.sh. A long-postponed improvement was suggested in #50724. Added switch --users to clickhouse-extract-from-config to get values from the users.xml. #75643 (Mikhail f. Shiryaev).