This PR will allow consumers to use a class definition style for defining experiments, instead of the existing .define method.

Working Example:

# frozen_string_literal: true
class SampleExperiment < Verdict::ExperimentDefinition
  qualify do
    true
  end

  groups do
    group :test, :half do
      description 'Test group'
    end

    group :control, :half do
      description 'Not in the experiment'
    end
  end
end

Advantages

• Each experiment is unique by default, and those Ruby constants can be accessed directly
• Compatible with autoload (e.g. all classes in app/experiment will be automatically loaded)
• Accessors are simpler. Instead of using the repository and doing something like Verdict[:sample_experiment].switch(), a more natural and ergonomic method of calling SampleExperiment.switch() can be used

The code requires cleanup, along with tests and README updates. The existing .define method is unchanged.

I am looking for feedback before making this rollout ready 👍