Python: Honor injected Foundry embedding clients without endpoint settings - #1

Motivation & Context

RawFoundryEmbeddingClient and FoundryEmbeddingClient rejected a caller-supplied embeddings SDK client unless a Foundry project or Models endpoint was also configured. Construction raised ValueError: Either 'project_endpoint', 'project_client', or 'endpoint' is required... even when text_client or image_client was already a working transport. Ambient FOUNDRY_MODELS_ENDPOINT could also become the wrapper service URL while requests still went to the injected client.

Callers who already own a configured EmbeddingsClient or ImageEmbeddingsClient should be able to embed with that client without also supplying an endpoint, API key, credential, dotenv file, or Foundry environment variables.

Description & Review Guide

An injected text or image SDK client is the transport for that modality. It takes precedence over constructor connection settings, environment settings, and framework defaults, so those settings are not required and are not used to replace the injected client. model and image_model keep the existing explicit-argument, environment, then default resolution.

When one modality is injected, the other is created only if a later request needs it and endpoint plus credential settings are available. Client factories are not called for a transport the caller already supplied. A missing modality with insufficient settings raises a focused ValueError at request time, before any partial request is sent. service_url() reads the endpoint stored on an injected Azure AI Inference client when that value is a string. Otherwise it uses an explicit endpoint argument, or reports an empty URL instead of substituting an ambient endpoint.

Caller-owned client cleanup is unchanged and remains covered by microsoft#9627.

• What are the major changes? Injected text_client / image_client values are sufficient transports in RawFoundryEmbeddingClient (and therefore FoundryEmbeddingClient). Connection settings are required only when a requested modality still has to be created.
• What is the impact of these changes? Callers that previously failed construction with only an injected client can now embed with that client. Existing project-client and Models-endpoint construction is unchanged when no SDK client is injected.
• What do you want reviewers to focus on? Precedence between an injected client, an explicit endpoint, and ambient Foundry endpoint settings, including service_url() when the SDK client does not expose a string endpoint.

Related Issue

Fixes microsoft#9950

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