🏗️ Upgrade to Nuxt 3

[rudokemper]

Closes #36.

This PR upgrades the application from Nuxt 2 to 3 (and by proxy an upgrade from Vue 2 to 3).

As the migration documents note, "Nuxt 3 is a complete rewrite of Nuxt 2, and also based on a new set of underlying technologies." Hence, upgrading touched nearly every part of the application.¹

Going granular on all of my changes would take me a long time, and I don't know that anyone is particularly keen on that level of detail; and much of it mirrors work in MapPacker on ConservationMetrics/map-packer#34.

However, what I would add is that this PR:

• Utilizes the gc-shared-resources library for things like middleware, components, auth.
• Makes much better use of the Composition API to logically organize blocks of code related to the same feature.
• Adds vitest tests for most of the API server logic that relates to filtering or transforming data.
• Makes a strong effort to improve typing for all server code.
• Resolves all eslint / typescript warnings and errors.
• Renames the application to "GuardianConnector Explorer"

What I'm not doing here:

Supporting building Docker images for arm in the Github workflows. Something about the refactor, or maybe the upgrade of the Docker image Node version, was breaking arm64, arm/v7 builds. So we'll have to figure that out later for Kakawa integration @luandro.

Footnotes

1. I don't have the reference handy, but at some point I watched a video of a presentation by Evan You, the creator of Vue.js & Vite, where he described that upgrades moving forward will be much less painful, thankfully. ↩