Switch objects from manual parsing to use Codable

[ryanbourneuk]

Expected Behaviour

Storm objects should be generated using Codable. This will allow us to use Swift object models to define the payload we're expecting, remove code that reduces type-safety, and allow errors to be easily surfaced when generating views at runtime.

Current Behaviour

Storm objects are generated with manual parsing / initialisation, removing type-safety and making issues harder to find.

Possible Solution

(only to be undertaken when test coverage is sufficient)

• Update storm view objects to use Codable
• Update storm localisation code to use Codable
• Update storm page objects to use Codable
• Update storm object generation to use Codable

Steps to Reproduce (for bugs)

Context

As part of the codable-refactor project, parts of the codebase (mainly storm object related) will be migrated from using manual JSON parsing / initialisation to using Codable. This will allow for increased type-safety, a reduction in boilerplate code, and the ability to easily surface errors when bundles are invalid.