Dispatch one on-demand run of this scout immediately, regardless of its schedule. Useful to test a scout right after authoring it, or to refresh its findings on demand. The run executes asynchronously on the worker and inherits every guard the scheduled path has: it is forbidden if scouts are not enabled for the project (403), and skipped if the project is over its Signals credits quota or daily run budget (429) or a run for this scout is already in progress (409). A manual run counts against the same daily run budget as scheduled runs, so repeated manual runs of the same scout can exhaust the project's daily allowance. A manual run does not change the scout's schedule or `last_run_at`. A disabled scout can still be run this way (to test before enabling). Returns immediately with the workflow id — poll the scout's runs for the result.