feat: exit_on_unhandled_faults config option; attempt to recover (or exit) after too long a period of inactivity

[tazlin]

• Sets the minimum required version of reGen to 4.2.4 due to the critical bug fixes it includes.
• Fixes a critical bug which occurs when a LoRa takes too long to download and can make the worker unstable
• Fixes LoRas retrying taking too long or retrying in doomed situations (such as missing a civitai token)
• Adds a fail-safe zombie detection:
  • If all processes have done nothing (or no jobs were submitted) for the amount of time set by process_timeout (900 seconds by default) AND the last pop pop message was a valid job pop (and not a "no jobs" message)
    • If exit_on_unhandled_faults is true
      • The worker attempts to exit as quickly as possible, not reporting any faults.
    • If exit_on_unhandled_faults is false (the default)
      • All of the inference processes are restarted and it tries to recover.
• Adds a good deal of logging to help diagnose future problems of this nature.