Performance and 'quality of life' tweaks

[vejvarm]

Hi, this is an awesome project. Thank you for making it!

If it's ok, I felt like tweaking the threading performance and also added a hotkey for terminating the program.

More specifically:

• Created main_thread function, that creates and handles the child threads of recording and transcribing.
• Changed the handling of filenames:
  • Now it creates files with random uuid names, instead of incrementing the names with integers. The functionality should remain the same.
• Replaced playsound package with playaudio package, which is more stable than the latest version of playsound
• Added F12 as hotkey for Terminating the program. Pushing F12 any time during the runtime should properly finish up the tasks and join all threads before finishing the run.
  • reasoning: in my case, when I wanted to turn off the program, it hanged and I had to kill it manually, because some of the threads wouldn't terminate and join with the main thread.

Let me know if there is anything wrong. I'll try to fix things up properly or just scrap this if you don't need it.