Setup feature flags & toggling

[daine]

📇 User story

As a developer, I want to have a configuration for feature toggling, so that I can continue to release code while working on a new feature.

✅ Definition of Done

• [x] Done when there is a configuration file or setting used for turning a feature on and off
• [x] At least one feature has been identified to be toggled
• [x] That feature is able to be turned on and off through configuration & redeployment
• [x] Documentation on feature flags is up to date

📜 Acceptance criteria

• [x] Strategy reviewed by all devs
• [x] Code reviewed and tested

📝 More info

There is an npm package nuxt-feature-toggle which we can use for this

[daine]

Grooming notes:

• The config could reside in an env variable
• We can use this for the menu (and could be used for A/B testing different menus)

[daine]

Documentation on usage in our wiki Architecture Decision Record on GDoc