pub const REDUCTION_METADATA_KEY: &'static str;Expand description
The reserved ChatMessage.metadata key carrying a reduced message’s
Reduction::id (the sc. prefix is reserved for this reduction
layer’s own bookkeeping).
This rides ChatMessage’s guarantee that metadata never serializes to
the wire (message.rs:49-54, 57-79) — the pointer reaches every
in-process consumer (CLI inspection, invert) but can never enter a
request body or a persisted transcript.