Hoist the three copies of apply_state_updates (llm, agent, rag) into
graph::state_updates::apply(state, output, has_schema, updates). The
helper computes every state_updates value first, restores the transient
`output` binding, and only then writes the computed updates, so a
`state_updates: { output: "{{output}}" }` entry is no longer clobbered
by the restore step.
The per-file wrappers stay as one-line calls so their existing tests are
unchanged; new direct helper tests live in state_updates.rs, including
the regression test for the clobber.
Design: plans/map-subgraph-branches-design.md §2.6, §3.7 (C5, D3).
Agent nodes marked teammates: true whose sub-agents run concurrently (map fan-out branches or multiple flagged agent nodes in one super-step) now form a team: each member gets a pre-provisioned inbox in a messaging-only PeerRegistry before any branch starts, a teammate roster injected into its prompt, peer resolution in agent__send_message, and a peers section in agent__list_running. Registries are scoped to a single fan-out and carry no lifecycle semantics: outputs still flow exclusively through collect_into/state reducers, finished peers reject new messages, and nothing registers in a supervisor. Also hardens the agent-recursion depth guard to work without a supervisor and adds validator warnings for zero-valued orchestration limits.
The supervisor registry went kind-generic (TaskHandle::Agent | Job)
earlier in this branch, but the module holding the agent__* handlers
and two model-facing error strings still carried the old name:
- src/function/supervisor.rs -> src/function/agents.rs (it contains
only agent__* tool handlers, pairing with function/jobs.rs; the
kind-generic src/supervisor/ registry keeps its name)
- 'Supervisor tool failed' -> 'Agent tool failed'
- 'Unknown supervisor action' -> 'Unknown agent action'
Dark-Alex-17