Migrate frontend to vue3 (part 1)

[mlbonhomme]

refs #2392

• compat build
• no more this.$set or filters
• vue-chartjs instead of vue-chartist which hasn't been updated in 3 years and caused warnings
• I wanted to take a look at what the stats page is supposed to look like but it doesn't seem to work ? so hopefully it looks like what it's supposed to look like