fix: include aiobotocore in the bedrock extra (#6419)

### Overview

`BedrockCompletion.acall()` (the async completion path used when a crew is kicked off asynchronously) requires `aiobotocore` to build its async client. The `bedrock` extra, however, only declared `boto3`. Crews configured with an AWS Bedrock model work fine under a synchronous `kickoff()`, since that path only needs `boto3`, but raise `NotImplementedError: Async support for AWS Bedrock requires aiobotocore` as soon as they're kicked off asynchronously, since `aiobotocore` was never installed.

The fix adds `aiobotocore` to the `bedrock` extra, so `crewai[bedrock]` installs both the sync (`boto3`) and async (`aiobotocore`) dependencies the native Bedrock provider needs. The lockfile is regenerated to match. The exception message is also corrected — it previously pointed to a `bedrock-async` extra that never existed in `pyproject.toml`.

### Changes

- `lib/crewai/pyproject.toml`: add `aiobotocore~=3.5.0` to the `bedrock` extra
- `uv.lock`: regenerated to reflect the updated `bedrock` extra
- `lib/crewai/src/crewai/llms/providers/bedrock/completion.py`: fix the install hint in the `NotImplementedError` message to reference the real `bedrock` extra instead of the nonexistent `bedrock-async`

lib/crewai/pyproject.toml

@@ -92,6 +92,7 @@ litellm = [
 ]
 bedrock = [
     "boto3~=1.42.90",
+    "aiobotocore~=3.5.0",
 ]
 google-genai = [
     "google-genai~=1.65.0",

lib/crewai/src/crewai/llms/providers/bedrock/completion.py

@@ -492,7 +492,7 @@ class BedrockCompletion(BaseLLM):
         if not AIOBOTOCORE_AVAILABLE:
             raise NotImplementedError(
                 "Async support for AWS Bedrock requires aiobotocore. "
-                'Install with: uv add "crewai[bedrock-async]"'
+                'Install with: uv add "crewai[bedrock]"'
             )
 
         with llm_call_context():