- ⚠️ `FrameProcessorSetup.pipeline_worker` and `FunctionCallParams.pipeline_worker` are now mandatory fields, and `FrameProcessor.pipeline_worker` raises if read before `setup()` instead of returning `None`. Real-world code (frame processors set up by `PipelineWorker`, tool handlers invoked by `LLMService`) is unaffected; only callers that construct these dataclasses by hand (typically tests) now have to supply a `pipeline_worker` reference.