In this PR (1/3) - introduce view.mainGroupByFieldMetadataId as the new reference determining which fieldMetadataId is used in a grouped view, in order to deprecate viewGroup.fieldMetadataId which creates inconsistencies. view.mainGroupByFieldMetadataId is now filled at every view creation, though not in use yet. - Introduce a command to backfill view.mainGroupByFieldMetadataId for existing views + delete all viewGroup.fieldMetadataId with a fieldMetadataId that is not view.mainGroupByFieldMetadataId. (It should concern 37 active workspaces) - Temporarily disable the option to change a grouped view's fieldMetadataId as for now it creates inconsistencies. This feature can be reintroduced when we have done the full migration. In a next PR - (2/3) use view.mainGroupByFieldMetadataId instead of viewGroup.fieldMetadataId. In FE we may keep viewGroup.fieldMetadataId as a state (TBD). View groups will now be created / deleted as a side effect of view's mainGroupByFieldMetadataId update. - (3/3) remove viewGroup.fieldMetadataId --------- Co-authored-by: Charles Bochet <charles@twenty.com>