[FEATURE] Built-in Automatic Retry & Backoff Middleware

[SB2318]

Confirmation of Request Source

• I confirm that this feature request is for the xAI SDK Python library (e.g., client features, SDK methods, or documentation) and not for the xAI API itself (e.g., model capabilities or API changes).

Describe the feature you'd like

Concept: Add customizable retry policies for gRPC rate limits (RESOURCE_EXHAUSTED) and transient network dropouts (UNAVAILABLE).

Why it matters: Network glitches and API rate limits currently throw unhandled gRPC errors. A built-in exponential backoff decorator makes production applications resilient out of the box.

Additional Context

Implementation Scope:

from xai_sdk import Client, RetryPolicy

client = Client(
    retry_policy=RetryPolicy(
        max_retries=3,
        backoff_factor=1.5,
        retry_on=[grpc.StatusCode.UNAVAILABLE, grpc.StatusCode.RESOURCE_EXHAUSTED]
    )
)