docs: document AWS (Assume Role) credential on Bedrock nodes

Author: its-imad

docs/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.embeddingsawsbedrock.md

@@ -18,7 +18,10 @@ You can find authentication information for this node [here](/integrations/built
 
 ## Node parameters
 
-* **Model**: Select the model to use to generate the embedding.
+* **Authentication**: Select the authentication method:
+    * **AWS (IAM)**: Use an IAM access key. Select an **AWS** credential.
+    * **AWS (Assume Role)**: Temporarily assume an IAM role. Select an **AWS (Assume Role)** credential.
+* **Model**: Select the model to use to generate the embedding. If the dropdown is empty, your IAM role may not have the `bedrock:ListFoundationModels` permission. Switch the field to **Expression** mode and enter the model ID directly.
 
 Learn more about available models in the [Amazon Bedrock documentation](https://docs.aws.amazon.com/bedrock/latest/userguide/what-is-bedrock.html). 
 

docs/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.lmchatawsbedrock.md

@@ -18,6 +18,9 @@ You can find authentication information for this node [here](/integrations/built
 
 ## Node parameters
 
+* **Authentication**: Select the authentication method:
+    * **AWS (IAM)**: Use an IAM access key. Select an **AWS** credential.
+    * **AWS (Assume Role)**: Temporarily assume an IAM role. Select an **AWS (Assume Role)** credential.
 * **Model**: Select the model that generates the completion.
 
 Learn more about available models in the [Amazon Bedrock model documentation](https://docs.aws.amazon.com/bedrock/latest/userguide/models-supported.html).

docs/integrations/builtin/credentials/aws.md

@@ -71,6 +71,7 @@ You can also generate access keys through the AWS CLI and AWS API. Refer to the
 
 You can use these credentials to authenticate the following nodes with enhanced security through IAM role assumption:
 
+* [AWS Bedrock Chat Model](/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.lmchatawsbedrock.md)
 * [AWS Certificate Manager](/integrations/builtin/app-nodes/n8n-nodes-base.awscertificatemanager.md)
 * [AWS Cognito](/integrations/builtin/app-nodes/n8n-nodes-base.awscognito.md)
 * [AWS Comprehend](/integrations/builtin/app-nodes/n8n-nodes-base.awscomprehend.md)
@@ -82,6 +83,7 @@ You can use these credentials to authenticate the following nodes with enhanced
 * [AWS SQS](/integrations/builtin/app-nodes/n8n-nodes-base.awssqs.md)
 * [AWS Textract](/integrations/builtin/app-nodes/n8n-nodes-base.awstextract.md)
 * [AWS Transcribe](/integrations/builtin/app-nodes/n8n-nodes-base.awstranscribe.md)
+* [Embeddings AWS Bedrock](/integrations/builtin/cluster-nodes/sub-nodes/n8n-nodes-langchain.embeddingsawsbedrock.md)
 
 ### Supported authentication methods