[CHORE] Make Ollama EF re-use connection

[rescrv]

Description of changes

Propel suggested using the reqwest pool. I'll do that.

Test plan

CI

Migration plan

N/A

Observability plan

N/A

Documentation Changes

N/A

[propel-code-bot]

Reuse Persistent HTTP Client in OllamaEmbeddingFunction

This PR refactors the OllamaEmbeddingFunction implementation in rust/chroma/src/embed/ollama.rs to eliminate the creation of a new reqwest::Client for every request. Instead, the HTTP client is now a field on the struct, instantiated once during construction and reused for all API interactions. This aligns the implementation with recommendations for using connection pooling for improved efficiency.

Key Changes

• Added a client: reqwest::Client field to the OllamaEmbeddingFunction struct.
• Modified the new constructor to create and store a single reqwest::Client.
• Refactored the EmbedRequest::make_request method to accept a reference to OllamaEmbeddingFunction (providing access to the shared client and host).
• Removed per-request instantiation of the reqwest::Client.
• Updated request creation and use throughout the embedding code to leverage the persistent client.

Affected Areas

• rust/chroma/src/embed/ollama.rs
• OllamaEmbeddingFunction struct and methods
• EmbedRequest request creation logic

This summary was automatically generated by @propel-code-bot

[github-actions]

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