Description

Adds the plumbing required for the upcoming GenerateEmbeddings query feature, which lets the gateway return query plans that contain parameterized embeddings (used by hybrid search).

Changes:

• QueryFeature.cs — adds a new GenerateEmbeddings = 1 << 17 flag to the internal QueryFeatures enum so the SDK can advertise / detect support for embedding-parameterized query plans.
• QueryInfo.cs — adds a new EmbeddingParameterMap (Dictionary<string, string>, serialized as embeddingParameterMap with NullValueHandling.Ignore) and a HasEmbeddingParameters convenience accessor on the internal QueryInfo model so query plans containing the new field round-trip correctly. Existing query plans without the field deserialize unchanged.
• QueryPartitionProviderTests.cs — adds two new cases to TestPartitionedQueryExecutionInfoDeserialization:
  1. A non-hybrid QueryInfo plan with an embeddingParameterMap, validating the new field round-trips through QueryPartitionProvider.ConvertPartitionedQueryExecutionInfo.
  2. A HybridSearchQueryInfo plan whose component QueryInfos each carry an embeddingParameterMap, validating the field round-trips when nested inside hybrid-search component query infos.
• Style fix — removes a duplicate blank line introduced near the new property to satisfy SA1507.

No public API surface change — both QueryFeatures and QueryInfo are internal in the released package. No SupportedQueryFeatures bitmask is flipped in this PR, so there is no behavior change for existing customer workloads on upgrade.

Type of change

• New feature (non-breaking change which adds functionality)

Closing issues

N/A

Changelog

• I have added a changelog entry under ### Unreleased in changelog.md for the user-facing impact of this change.
• No changelog entry is required because this PR is one of: documentation-only, test-only, CI / build-only, or a pure internal refactor with no observable customer impact.

If the second box is checked, briefly justify here:

Internal-only plumbing. QueryFeatures and QueryInfo.EmbeddingParameterMap are both internal types in the released package. This PR does not add GenerateEmbeddings to any SupportedQueryFeatures bitmask, and the new property uses NullValueHandling.Ignore so query plans that don't include embeddingParameterMap deserialize identically to before. There is no
customer-observable behavior change on upgrade.