Function process_output_refs 

pub fn process_output_refs(value: &mut Value) -> Vec<OutputRefDep> 

Process task output references in raw JSON before deserialization.

Walks the tasks subtree of a CUE-evaluated JSON value and:

1. Replaces #TaskOutputRef objects in args and env with placeholder strings
2. Strips computed stdout/stderr/exitCode fields from task objects
3. Returns dependency pairs for auto-dependency inference

This must be called on raw serde_json::Value BEFORE deserializing into Task structs, because ref objects would fail Vec<String> deserialization.