4929: Add facets support to federated r=Kerollmops a=dureuill
# Pull Request
## Related issue
- Fixes#4932 (sprint issue)
- Fixes #4913 (user-opened issue)
## What does this PR do?
See [public usage](https://meilisearch.notion.site/v1-11-Federated-search-59b30e03383c40729d7541a3dffb0069)
> [!CAUTION]
> This PR introduces a 🚨**breaking change**🚨: `queries.facets` when `federation` is present and non-`null` is now **an error**
### Implementation standpoint:
- Facet distribution: fix issue where truncated facet distribution would have a wrong order
- facet distribution: implement Display for OrderBy
Co-authored-by: Louis Dureuil <louis@meilisearch.com>
4912: Allow Meilitool to dumplessly, offline upgrade v1.9 -> v1.10 in some conditions r=Kerollmops a=dureuill
- bail early if the DB contains at least 1 REST embedder, providing the list of detected REST embedders, and without modifying the DB
- Might depend on the feature set that meilitool was compiled with and the featureset that the Meilisearch that created the DB was compiled with 💀. In case of runtime error, try again with a different feature set (passing or not passing `-p meilitool` when building after a `cargo clean`)
Co-authored-by: Louis Dureuil <louis@meilisearch.com>
4536: Limit concurrent search requests r=ManyTheFish a=irevoire
# Pull Request
## Related issue
Fixes https://github.com/meilisearch/meilisearch/issues/4489
## What does this PR do?
- Adds a « search queue » that limits the number of search requests we can process at the same time and stores search requests to be processed
- Process only one search request per core/thread (we use available_parallelism)
- When the search queue is full, new search requests replace old ones **randomly**. The reason is that:
- If we serve the oldest one first, like Typesense, we give the worst performances to everyone
- If we serve the latest one, it gets too easy to DoS us (you just need to fill the queue with as many search requests as we can process simultaneously to ensure no other request will ever be processed)
- By picking the search request randomly, we give a chance to recent search requests to be processed while ensuring that we can't be owned unless they fill our queue entirely and we start returning errors 5xx
- Adds an experimental parameter to control the size of the queue
- Adds a bunch of tests to ensure the search queue works correctly
- Ensure the loop consuming the search queue is running in the health route and crashes if it’s not the case
Co-authored-by: Tamo <tamo@meilisearch.com>
