Improve user and group setup in clp-package Docker image

[coderabbitai]

Context

This issue tracks improvements to the user and group creation process in the clp-package Docker image, as discussed in PR #1414.

Background

During review of PR #1414, it was suggested that the Docker image could benefit from proper group creation and a more realistic user home environment setup. The current implementation creates a user but does not create a dedicated group or set up a traditional home directory structure.

Suggested Improvements

• Add group creation with configurable GID
• Create user with proper group assignment
• Set up a traditional home directory under /home/
• Make UID and GID configurable as build arguments

References

• PR: fix(docker): Include libmariadbcpp.so (required by spider_scheduler and spider_worker) in the clp-package image; Set mariadb-connector-cpp build type to Release (fixes #1410). #1414
• Comment: fix(docker): Include libmariadbcpp.so (required by spider_scheduler and spider_worker) in the clp-package image; Set mariadb-connector-cpp build type to Release (fixes #1410). #1414 (comment)
• Requested by: @junhaoliao

Notes

These changes were deferred from PR #1414 to keep that PR focused on making the spider binaries work. PR #1413 already made some initial user creation changes.