Support more facets types

[alexgarel]

What

• Currently facets are terms queries, but it is not adapted to all situations, we might want histograms (to render as range), significant_terms, etc.

Proposed solution

I propose:

• in configuration, to change the bucket_agg from a boolean to a string specifying agg type. We could even have a dict to propose more than one type in some case (eg a facet categories_tags.significants for significant terms, or maybe we specify it in the request)
• we may have to change filter analysis to retrieve selected values (whatever it means)
• we have to develop the specific widgets

Forseen facets:

• range for nutrients
• significants terms are worth trying for categories

Tasks

Preview Give feedback

1. Enable using a term facet with significant_terms aggregation (API + webcomponent)
2. Range facet for numeric fields and/or few value (a,b,c…) #182
   0 of 3
   side panel +1
3. facets with some values associated with images (eg. ecoscore logo)

Part of

• 🎯 What can I work on ? (search-a-licious) #62