fix: Catch OSError when importing AnthropicLlm

PiperOrigin-RevId: 912711824

Author: google-genai-bot

src/google/adk/flows/llm_flows/contents.py

@@ -57,7 +57,7 @@ async def run_async(
         # ids must survive replay.
         try:
           from ...models.anthropic_llm import AnthropicLlm
-        except ImportError:
+        except (ImportError, OSError):
           AnthropicLlm = None
         if AnthropicLlm is not None and isinstance(
             canonical_model, AnthropicLlm