Discriminated union over the run mode: exactly one of the backtest,
paper or live flags picks the pipeline Worker.run starts in the forked
child process owning the whole symbol list of the call.
workerName — registry key; duplicate registration is a validation error.
strategyName / exchangeName / frameName — optional: when omitted, the
SINGLE registered schema of that kind is used; with two or more
registered the worker must name one explicitly — ambiguity is an
error, not a guess.
callbacks — all optional; an omitted callback is simply never fired.
Registration schema of a worker instance.
Discriminated union over the run mode: exactly one of the backtest, paper or live flags picks the pipeline Worker.run starts in the forked child process owning the whole symbol list of the call.