[v1.8] Hybrid search improvements

[curquiza]

Related to https://github.com/meilisearch/integration-guides/issues/299

Quick explanation of the changes

Related issue in the engine: https://github.com/meilisearch/meilisearch/issues/4481

⚠️ Refer to

• the usage page for any details about the changes: https://meilisearch.notion.site/v1-8-AI-search-API-usage-135552d6e85a4a52bc7109be82aeca42?pvs=4
• for a more global and less "digest" overview of the changes (but less precise) check the in-progress changelog: https://github.com/meilisearch/engine-team/pull/64/files

Summary of changes:

• Handle breaking changes about search
  • vector is not longer displayed in the search response
  • _semanticScore is no longer returned in the search response
  • When adding "showRankingScoreDetails": true to a semantic search query, the vector and its value are no longer displayed
• Add new models
  • REST embedder
  • Ollama
• Addition of distribution field in settings
• New semanticHitCount field in search response
• Now Meilisearch hides API key

TODO

• [ ] Ensure breaking changes fit in the code base. It's about removing fields, so "fit in the code base" means
  • [ ] Ensure the code base does not expect any of these fields
  • [x] Fix the tests (if any are broken because of these changes)
• [ ] Ensure the support of the new models rest and ollama
• [x] Ensure the support of the distribution field in index settings for embedders
• [x] Ensure the support of the semanticHitCount in the search response for hybrid/semantic search
• [x] Now Meilisearch hides API key: fix the elated tests.
• [ ] Add tests for each of these additions

⚠️ Make PRs pointing to bump-meilisearch-v1.8.0 and NOT main. Please do 1 PR for all of these changes, and not several.

[DRN88]

Please add support for hybrid in FacetSearchQuery. I had to extend that class to make it work with vector search. Thanks.

Example:

Meilisearch\Contracts\FacetSearchQuery

public function setHybrid(array $hybrid): FacetSearchQuery
{
    $this->hybrid = $hybrid;

    return $this;
}

setHybrid([
    'semanticRatio' => 0.5,
    'embedder' => 'default'
]);

[brunoocasali]

Hi @DRN88, I'm not sure if I followed you want to use the vector search in the facetSearch but it is not supported https://www.meilisearch.com/docs/reference/api/facet_search

[curquiza]

Closed by #639