Refactoring events, adding testing frameworks

[ondrej33]

This small PR deals with various little things:

• Some code refactoring relevant to events (defining constants, removing unused code...)
• The tool's name is changed from the outdated AEON Sketchbook to Biodivine Sketchbook
• There is a new installation guide and instructions in the README.
• There is a prototype for the new vitest-based framework for front-end unit tests.
• There is a prototype for a new selenium-based framework for end-to-end tests.
• New dependencies versions.
• Added a new button to re-render a help message at the network editor.
• Some names for properties/tabs were changed.
• Messages for errors due to issues in formula parsing were updated.