Owned work¶
The serial executor owns Send + 'static tasks and captures. Pending capacity
excludes the running task. Full/stopped queues reject work without executing
it; destruction drains accepted work. Panics are contained, though the normal
panic hook can report them. Last-owner teardown inside a worker safely detaches
the join handle. There is no UI dispatch or real-time scheduling guarantee.
Worker timers serialize callbacks, wait one interval before the first tick, skip catch-up bursts and stop before normal teardown returns. Rust callbacks own their captures. Callbacks must return; stopping cannot cancel blocked work. These worker timers do not replace host UI-loop timers.