feat(Product Map): Add prices count and average to map

[TTalex]

What

• In product details, when displaying prices as a map, adds count and average prices for each location
• This new line appears in the popup when clicking on a map marker
• This line is stored in a generic "info" parameter, to keep LeafletMap component reusable
• The count and average matches the loaded prices (25 by default, more when scrolling)

Screenshot

Next Step

• It's a bit odd to average organic and non-organic products. We should either display them in two lines, or wait for an "organic" filter.
• Mixed unit (per kg / per unit) might also be an issue for some categories
• Mixed currencies shouldn't be an issue, it's unlikely for shops to use more than one currency

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Files not reviewed (1)

• src/i18n/locales/en.json: Language not supported

Comments skipped due to low confidence (1)

src/views/ProductDetail.vue:243

• The use of template literals with new lines might introduce unintended whitespace. Consider removing the new lines within the template literal.

location.info = `\n ${this.$t('Common.PriceCount', { count: priceLocationTotal.count })}. \n ${this.$t('Common.Average')}: ${utils.prettyPrice(priceLocationTotal.total / priceLocationTotal.count, priceLocationTotal.currency)}. \n `