[Feature]: Allow setting up Req Attachments without the need of using low level API

[ycastorium]

Feature Type

Core library enhancement

Provider (if applicable)

No response

Description

Of course, we can always use the low-level API, but this would need to reimplement the whole high-level API just to add REQ plugins, so lets just allow REQ Plugins to be set!

Example Usage

{:ok, req} = ReqLLM.generate_text("yada yada", req_plugins: [&MyPlugin.attach/1])

Can you contribute this?

Yes, I can submit a PR