Metrics feature was relying on old references. Refactored with inspiration from the `get_stats` method in `meilisearch/src/routes/lib.rs`. `enable_metrics_routes` added to options in `segment_analytics`.
Resolves: #3469
See also: #2763
As reported the metrics feature was broken by still using and old reference to `meilisearch_auth::actions`. This commit switches to the new location, `meilisearch_types::keys::actions`.
Resolves: #3469
See also: #2763