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- add `debug_1`, `debug_2` etc as additional log levels
- socket cleanup for ZMQ connections
- add ZMQ registry class with dict interface
- added test for `zmq.client` and applied corresponding fixes
- add type annotations
- support for task env isolation
- damonize server threads
- disabled `os.setsid` in `ru.daemonize`
- improved flux integration (flux executor API)
- reconnect to external flux instances
- cleanup and fix host helper methods