feat!: change bedrock bearer token env variable to match AWS docs & boto3 convention (#4152)

Rename `AWS_BEDROCK_API_KEY` to `AWS_BEARER_TOKEN_BEDROCK` to align with
the naming convention used in AWS Bedrock documentation and the AWS web
console UI. This reduces confusion when developers compare LLS docs with
AWS docs.

Closes #4147

src/llama_stack/providers/remote/inference/bedrock/bedrock.py

@@ -37,7 +37,7 @@ class BedrockInferenceAdapter(OpenAIMixin):
     """
 
     config: BedrockConfig
-    provider_data_api_key_field: str = "aws_bedrock_api_key"
+    provider_data_api_key_field: str = "aws_bearer_token_bedrock"
 
     def get_base_url(self) -> str:
         """Get base URL for OpenAI client."""
@@ -111,7 +111,7 @@ class BedrockInferenceAdapter(OpenAIMixin):
                 logger.error(f"AWS Bedrock authentication token expired: {error_msg}")
                 raise ValueError(
                     "AWS Bedrock authentication failed: Bearer token has expired. "
-                    "The AWS_BEDROCK_API_KEY environment variable contains an expired pre-signed URL. "
+                    "The AWS_BEARER_TOKEN_BEDROCK environment variable contains an expired pre-signed URL. "
                     "Please refresh your token by generating a new pre-signed URL with AWS credentials. "
                     "Refer to AWS Bedrock documentation for details on OpenAI-compatible endpoints."
                 ) from e

src/llama_stack/providers/remote/inference/bedrock/config.py

@@ -12,9 +12,9 @@ from llama_stack.providers.utils.inference.model_registry import RemoteInference
 
 
 class BedrockProviderDataValidator(BaseModel):
-    aws_bedrock_api_key: str | None = Field(
+    aws_bearer_token_bedrock: str | None = Field(
         default=None,
-        description="API key for Amazon Bedrock",
+        description="API Key (Bearer token) for Amazon Bedrock",
     )
 
 
@@ -27,6 +27,6 @@ class BedrockConfig(RemoteInferenceProviderConfig):
     @classmethod
     def sample_run_config(cls, **kwargs):
         return {
-            "api_key": "${env.AWS_BEDROCK_API_KEY:=}",
+            "api_key": "${env.AWS_BEARER_TOKEN_BEDROCK:=}",
             "region_name": "${env.AWS_DEFAULT_REGION:=us-east-2}",
         }