[WIP][EGS]: Add azure-cosmos-ai companion package with Azure OpenAI embedding provider

[aayush3011]

Description

Introduces a new sibling package, azure-cosmos-ai (1.0.0b1), that ships the default Azure OpenAI implementation of the EmbeddingProvider Protocol introduced in azure-cosmos 4.16.0b3. The provider is used by the Cosmos SDK to generate vector embeddings at query time for GenerateEmbeddings(...) expressions on containers whose vectorEmbeddingPolicy.embeddingSource points at an Azure OpenAI deployment.

What's in the package

• azure.cosmos.ai.AzureOpenAIEmbeddingProvider (sync) and azure.cosmos.ai.aio.AzureOpenAIEmbeddingProvider (async).
• Three credential shapes per surface:
  • str (raw Azure OpenAI API key)
  • azure.core.credentials.AzureKeyCredential
  • TokenCredential (sync) / AsyncTokenCredential (async) for Entra/RBAC, wired through get_bearer_token_provider against https://cognitiveservices.azure.com/.default.
• Per‑endpoint client caching, context‑manager support, and idempotent close() that releases the cached AzureOpenAI / AsyncAzureOpenAI client(s).
• Empty texts short‑circuits without a network call and returns an EmbeddingResult with vectors=[], total_tokens=0, latency=0.0.

Tests

Each test module exposes two pytest classes:

• TestAzureOpenAIProvider / TestAzureOpenAIProviderAsync: 12 fully mocked unit tests; always collected.
• TestAzureOpenAIProviderLive / TestAzureOpenAIProviderLiveAsync: 5 opt‑in live tests against a real Azure OpenAI resource. Gated by COSMOS_AI_LIVE_TESTS=1 plus AZURE_OPENAI_ENDPOINT, AZURE_OPENAI_EMBEDDING_DEPLOYMENT, AZURE_OPENAI_EMBEDDING_DIMENSIONS, and (for API‑key paths) AZURE_OPENAI_API_KEY. Covers raw key, AzureKeyCredential, DefaultAzureCredential, the empty‑texts short‑circuit, and per‑endpoint client caching.

Related

Companion to the EGSInterface and EGSPolicy work on azure-cosmos (EmbeddingProvider Protocol, EmbeddingResult dataclass, and the new embeddingSource fields on VectorEmbeddingPolicy).

All SDK Contribution checklist:

• The pull request does not introduce [breaking changes]
• CHANGELOG is updated for new features, bug fixes or other significant changes.
• I have read the contribution guidelines.

General Guidelines and Best Practices

• Title of the pull request is clear and informative.
• There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• Pull request includes test coverage for the included changes.

[Copilot]

Pull request overview

This PR introduces a new sibling package, azure-cosmos-ai (1.0.0b1), which provides a default Azure OpenAI-backed implementation of the EmbeddingProvider contract used by azure-cosmos to generate vector embeddings for GenerateEmbeddings(...) query expressions.

Changes:

• Adds new azure-cosmos-ai package with sync/async AzureOpenAIEmbeddingProvider, credential support, endpoint-based client caching, and close/context-manager behavior.
• Adds unit tests (mocked) plus opt-in live tests, and provides samples + README + changelog for the new package.
• Updates Cosmos service CI artifact list to include azure-cosmos-ai.

Reviewed changes

Copilot reviewed 21 out of 22 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
sdk/cosmos/ci.yml	Adds azure-cosmos-ai to the Cosmos CI artifact list.
sdk/cosmos/azure-cosmos-ai/tests/test_azure_openai_provider.py	Sync unit + opt-in live tests for the provider.
sdk/cosmos/azure-cosmos-ai/tests/test_azure_openai_provider_async.py	Async unit + opt-in live tests for the provider.
sdk/cosmos/azure-cosmos-ai/tests/conftest.py	Test-time stub injection for EmbeddingResult (for local/CI compatibility).
sdk/cosmos/azure-cosmos-ai/setup.py	Package setup/configuration and dependencies.
sdk/cosmos/azure-cosmos-ai/sdk_packaging.toml	Packaging automation configuration.
sdk/cosmos/azure-cosmos-ai/samples/sample_embedding_provider.py	Sync usage sample showing API key and Entra scenarios.
sdk/cosmos/azure-cosmos-ai/samples/sample_embedding_provider_async.py	Async usage sample showing API key and Entra scenarios.
sdk/cosmos/azure-cosmos-ai/README.md	Package overview, examples, credential matrix, troubleshooting notes.
sdk/cosmos/azure-cosmos-ai/pyproject.toml	Enables repo build checks (mypy/pylint) for this package.
sdk/cosmos/azure-cosmos-ai/MANIFEST.in	Source distribution include rules (samples/tests/namespace files/py.typed).
sdk/cosmos/azure-cosmos-ai/LICENSE	MIT license file for the package.
sdk/cosmos/azure-cosmos-ai/dev_requirements.txt	Dev dependencies for local builds/tests.
sdk/cosmos/azure-cosmos-ai/CHANGELOG.md	Initial release entry for 1.0.0b1 (Unreleased).
sdk/cosmos/azure-cosmos-ai/azure/cosmos/ai/py.typed	Marks the package as typed.
sdk/cosmos/azure-cosmos-ai/azure/cosmos/ai/aio/_azure_openai_provider.py	Async Azure OpenAI provider implementation.
sdk/cosmos/azure-cosmos-ai/azure/cosmos/ai/aio/init.py	Exposes async provider class.
sdk/cosmos/azure-cosmos-ai/azure/cosmos/ai/_version.py	Package version constant.
sdk/cosmos/azure-cosmos-ai/azure/cosmos/ai/_azure_openai_provider.py	Sync Azure OpenAI provider implementation.
sdk/cosmos/azure-cosmos-ai/azure/cosmos/ai/init.py	Exposes provider + __version__.
sdk/cosmos/azure-cosmos-ai/azure/cosmos/init.py	Introduces an azure.cosmos package initializer (namespace-style).
sdk/cosmos/azure-cosmos-ai/azure/init.py	Introduces an azure package initializer (namespace-style).