Migrate web demo to more recent tooling

[sbernard31]

When we create the first version of demos based on vuejs (https://github.com/eclipse-leshan/leshan/pull/977), the recommended version to use was :

• vuetify 2 (only stable one available, only compatible with vue 2)
• vue 2
• vue-cli (default scafolding tooling for vuetify 2)
• yarn classic (to be easily used with maven-frontend-plugin)

One day, we should migrate to more recent version of this :

• vuetify 3 (compatible with vue 3)
• vue 3
• vite which replace vue-cli
• yarn modern (v3 or v4)

Looking quickly at documentation this will not be straightforward migration.

Hoping this could improve build performance issue. (see : https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/issues/3429#note_1199991)

	From	To	Issue
✅	vue-cli	Vite	~https://github.com/eclipse-leshan/leshan/issues/1540~
☐	yarn-classic	Yarn 4	https://github.com/eclipse-leshan/leshan/issues/1550
☐	Vue 2 Vuetify 2	Vue 3 Vuetify 3

[sbernard31]

Maybe this could also have impact on : https://github.com/eclipse-leshan/leshan/issues/1016

[sbernard31]

About migrating from vue-cli to vite:

• https://vueschool.io/articles/vuejs-tutorials/how-to-migrate-from-vue-cli-to-vite/
• https://kingyue737.github.io/vitify-docs/guide/migration.html (vuetify 2)
• https://blog.boot.dev/javascript/migrating-vue-webpack-to-vitejs/
• https://moiva.io/blog/the-missing-migration-guide-from-vue-cli-to-vite/

[sbernard31]

Trying to move from vue-cli to vite and didn't succeed for now.

Also disover that Vue 2 will reach End of Life (EOL) on December 31st, 2023. And I didn't really get what is HeroDevs’ NES (Never-Ending Support) for Vue 2.

Note that vuetify 2 is only compatible with vue2 and vuetify 3 is only compatible with vue3 (so both should be migrate together) vite should works with both.

[sbernard31]

I created dedicated issue about migrating from vue-clito vite : https://github.com/eclipse-leshan/leshan/issues/1540

[sbernard31]

I create dedicated issue about migration from yarn-classic to yarn stable (4) : https://github.com/eclipse-leshan/leshan/issues/1550