Is your feature request related to a problem? Please describe.
Claude LLM throws NotImplementedError error when being provided pdfs in version = "1.16.0".

Describe the solution you'd like
A new type in anthropic_types can be added for PDFs and in adk/models/anthropic_llm.py", function part_to_message_block, an extra if condition for PDFs

Describe alternatives you've considered
For now, I manually modify context: InvocationContext to remove Parts from ctx.user_content that have "mime_type" == "application/pdf"

Since Claude models (e.g. Claude Sonet 4.5) support input PDF files, this would be a nice feature to have in ADK. Thanks