Merge https://github.com/google/adk-python/pull/1451
## Description
Fixes https://github.com/google/adk-python/issues/1306 by using `async for` with `await self.llm_client.acompletion()` instead of synchronous `for` loop.
## Changes
- Updated test mocks to properly handle async streaming by creating an async generator
- Ensured proper parameter handling to avoid duplicate stream parameter
## Testing Plan
- All unit tests now pass with the async streaming implementation
- Verified with `pytest tests/unittests/models/test_litellm.py` that all streaming tests pass
- Manually tested with a sample agent using LiteLLM to confirm streaming works properly
# Test Evidence:
https://youtu.be/hSp3otI79DM
Let me know if you need anything else from me for this PR
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/1451 from avidelatm:fix/litellm-async-streaming d35b9dc90b2fd6fad44c3869de0fda2514e50055
PiperOrigin-RevId: 774835130
Merge https://github.com/google/adk-python/pull/1079
Fixes part of #356
Add usage attributes to span.
Note: Since the handling of GenAI event bodies in OpenTelemetry has not yet been determined, I have temporarily added only attributes related to usage.
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/adk-python/pull/1079 from soundTricker:feature/356-support-more-opentelemetry-semantics 99a9d0352b4bca165baa645440e39ce7199f072b
PiperOrigin-RevId: 774834279
This change accepts the `google.auth.credentials.Credentials` type for `BigQueryCredentialsConfig`, so any subclass of that, including `google.oauth2.credentials.Credentials` would work to integrate with BigQuery service. This opens up a whole range of possibilities, such as using service account credentials to deploy an agent using these tools.
PiperOrigin-RevId: 773190440
