This is the next step to clean up the Ctrl+C / Agent stopping, pausing, and resuming code.

• determine if we even need Agent.state.paused anymore now that we are using a threadsafe Agent._external_pause_event semaphore. I think we should simply that to just the semaphore and store it in Agent.state
• we should review the code to see if all these methods and state attrs really need to be separate, or if we can merge them somehow all into one pair of methods & one state attr:
  • Agent.pause()/Agent.resume() -> Agent.state.paused
  • Agent.stop() -> agent.state.stopped
  • Agent._external_pause_event

Related PRs:

• Support multi-thread agent execution including pause,resume operations  #1466 (comment)
• Pause blocks the main thread of process, is it possible to do it in non blocking way and bypass the keyboard interrupt? #1704
• Fix: Terminal reset sequence when exiting with Ctrl+C  #1534
• Add windows support to ctrl+C handling #1192
• [Fix] Handle RuntimeError: Event loop is closed (#219) #816
• Refactor ctrl-c handling to separate class #1179
• Verify LLM API keys work on startup and add Ctrl+C error handling #1178