Integrate property-based testing with StreamData

[Kavignon]

Description

Implement property-based testing in the Elixir-Kickoff template using the StreamData library. This integration should include:

• Data generation: Utilize StreamData to create generators for various data types, enabling the production of diverse input scenarios for testing.
• Property testing: Define properties the code should satisfy universally and employ StreamData to validate these properties across numerous generated inputs.
• Documentation and examples: Develop examples demonstrating leveraging StreamData for property-based testing within the template. This should include:
  • Basic usage of StreamData for generating data.
  • Crafting property-based tests using StreamData.
  • Interpret test results and understand the concept of shrinking.
  • Include links to the official StreamData documentation and relevant articles to deepen users' understanding.