fn sender_identity(slot: &SessionSlot) -> (String, String)Expand description
The name and org an envelope carries for the session that sent it,
derived from that session’s own slot: the project for a project’s own
agent, project/label for a worker, with the org beside it.
Derived rather than delegated to an engine, because one identity has to hold on every path - the two engines answered this differently, the in-project one by label and the cross-project one by project, so a single worker rendered as two senders depending on which path carried its message. The label is what keeps a worker distinguishable from its own lead at all: without it a worker messaging another project carried the bare project name, which is exactly what its lead sends.