feat: MetricsDataProvider (#1932)

* Adding a first stab at the MetricsDataProvider, which models how we
  did it with the EventDataProvider, with a couple changes
* We now just get the metadata for metrics and projects/artifacts in the
  same query, so we don't need to do multiple round trips to the API
* We bundle the metric and project/artifact name into the event data so
  we don't have to do multiple lookups
* We create a meta MetricsDataProvider which switches on the entityType
* Because of these refactors, I was able to remove some utility
  functions we don't use anymore

apps/frontend/.env.local.example

@@ -16,13 +16,19 @@ NEXT_PUBLIC_DOMAIN=www.opensource.observer
 ### GraphQL API endpoint for database (required)
 NEXT_PUBLIC_DB_GRAPHQL_URL=
 HASURA_URL=
+HASURA_PAT=
 ### OSO API key
 OSO_API_KEY=
 ### Supabase for database (required)
 NEXT_PUBLIC_SUPABASE_URL=
 NEXT_PUBLIC_SUPABASE_ANON_KEY=
 SUPABASE_SERVICE_KEY=
 SUPABASE_JWT_SECRET=
+### Clickhouse for OLAP database (required)
+CLICKHOUSE_URL=
+CLICKHOUSE_USERNAME=
+CLICKHOUSE_PASSWORD=
+CLICKHOUSE_DB_NAME=
 ### Algolia for search (required)
 NEXT_PUBLIC_ALGOLIA_APPLICATION_ID=
 NEXT_PUBLIC_ALGOLIA_API_KEY=