Add multimodal support to Bedrock Converse integration #1887
Description
The Bedrock Converse integration should support multimodal inputs including documents (PDF, DOC, etc.), images (JPEG, PNG, etc.), and videos (MP4, MOV, etc.). This will enable users to interact with the Bedrock AI models using various media types. Update BedrockProxyChatModel to handle multimodal content
Related: AWS Bedrock Multimodal API documentation