Active goal loops can stay inside one agent run while the model keeps
emitting tool calls, so the normal agent_end threshold maintenance never
runs. That lets context grow past the soft threshold until provider
overflow or user abort.
Run threshold maintenance from the per-turn onTurnEnd hook for active
goals, splice the compacted agent state back into the live loop message
array, and suppress queued continuations because the current run is
already continuing. Cover the mid-run tool-call path and the non-goal
control case.
Refs #3174
Alexander Kirilin