Possibility of adding pomodoro-length entries

[kiinami]

This pull request introduces new functionality to the main.py file, specifically adding support for creating Pomodoro time entries that end at the moment of entry (thus starting 25 minutes before that). The most important changes include importing necessary modules, adding new methods to handle Pomodoro time entries, and modifying the event handling to support these new features.

Pomodoro Time Entry Support:

• Module Import:

  • Added timedelta import from the datetime module to handle time calculations.

• Event Handling:

  • Modified the on_event method to insert new items for creating Pomodoro time entries when the query starts with 'pd'.
  • Added handling for resume_pomodoro and new_pomodoro calls in the on_event method.

• New Methods:

  • Added get_time_minus_offset method to calculate the time minus a specified offset in minutes.
  • Added add_pomodoro_time_entry method to create a new Pomodoro time entry, either resuming the last entry or creating a new one with a specified message.