ErrorKit: Dynamic runtime error mapping

[Jeehut]

Problem addressed:

A lot of boilerplate code is needed to throw properly in functions that could go wrong.

Uniquely identify each kind of error and report it to a backend where developers can – during runtime – map the errors to their custom error messages to be shown to users (built-in localizer). The SDK loads these upon app start or refreshes if needed to always have the latest mappings. We could even provide our own over time directly available in the SDK.

Note that the backend will be only a hook in the ErrorKit library, no backend is provided. FeedbackKit provides that. Including the localization needed for it.

[Jeehut]

This should probably tackled together with the FeedbackKit server functionality related (mapping errors to messages).