UserMessage upload PDF cannot read

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Bug description
When I use an LLM model, such as ChatGPT, and upload a PDF document, the media cannot access the resources

Environment
jdk21, spring-ai-1.1.0

Steps to reproduce
Media media = new Media(mediaType != null ? mediaType : MediaType.ALL, new URI(filePath));
Upload a PDF file and then send a question, such as asking what the content of the document uploaded by the large model is. It will respond that no document or image has been uploaded

Expected behavior
For the example above, I hope to retrieve the content from the document

Minimal Complete Reproducible example

and chatClient.prompt(prompt).stream().content()

Start with the Media construction using new URI(filePath) and the chatClient.prompt(...).stream().content() reproduction; inspect how PDF media is passed to the configured LLM. Done means a PDF upload's content is available when asking a question, with a regression test for the reported jdk21/spring-ai-1.1.0 case.