Upgrade to Vue 3 and the Composition API

[rydurham]

This PR upgrades this project to be compatible with Vue 3. There are some notable changes:

• We are now using Three.js directly instead of the Three-Full wrapper package.
• We are using the Vue 3 composition API and component <script setup> wherever possible.
• Based on @Camil88's research most of the Three.js elements are added to the store with the markRaw helper. This is a recommended best practice for storing non-reactive elements in state. Eliminating reactivity where it is not needed should help lower overall memory usage and improve performance.
• Rather than upgrade to the latest version of Vuex this PR uses Pinia for state management, which is the new preference in the Vue community.
• HMR has been disabled; I have noticed some memory issues that seem to be aggravated by HMR. This may require further investigation. In theory this should not impact an application in production.
• I have included a docker setup for those who are interested - this is optional.