When calculating sentence probability, perform a run for a limited dataset

[acnicholls]

Is your feature request related to a problem? Please describe.
most real life sentences when encrypted this way have trillions of permutations when decrypted, it will consume 100% CPU for days, weeks or even months to perform a decryption

Describe the solution you'd like
have the ability to select a timed run or a number of permutations to test before shutting down

• for timed run
  • accept a number of minutes to run for
  • report the number of permutations checked when complete
• for a number run
  • accept a number of permutations to check
  • show a progress bar until completion
• when selecting the permutations to run make sure they haven't been run already
• add an option to clear all probabilities

Describe alternatives you've considered
leaving the application as is

Additional context