fix: threadsafe lob_print

[MrKevinWeiss]

This pull request improves thread safety and reliability in the logging setup of the lob_print function by introducing a lock to prevent race conditions when multiple threads attempt to configure file handlers simultaneously. Additionally, it clarifies the logic for attaching handlers to loggers. The most important changes are:

Thread safety improvements:

• Added a threading.Lock (_log_handler_lock) to protect the one-time setup of rotating file handlers in lob_print, ensuring that concurrent threads do not create duplicate handlers or encounter race conditions. [1] [2] [3]

Logging handler setup adjustments:

• Modified the logic for adding file handlers so that handlers are added to both the root logger (for propagation) and the specific logger (since propagate=False), ensuring correct logging behavior.

[Copilot]

Pull request overview

Improves reliability of LobHlpr.lob_print() logging by making rotating file handler setup thread-safe and clarifying how handlers are attached to ensure logs are written even with propagate=False.

Changes:

• Added a module-level lock to prevent concurrent threads from creating duplicate RotatingFileHandlers.
• Switched handler detection to use an absolute log path and re-check under the lock.
• Adjusted handler attachment to include both the root logger and the lob_hlpr logger.

[MrKevinWeiss]

A few extra things that are nice, but not really that needed...