BaseTask.handoff_to was just deactivate_self + activate_task. Remove
it and add a deactivate_self flag on activate_task instead, so there's
one entry point for activating another task.
LLMTask now overrides activate_task (mirroring its end() override) to
keep the messages / result_callback hooks that finish an in-progress
tool call before the target is activated. All multi-task examples and
unit tests switch to the new call.
Rename ``_build_greeter`` / ``_build_support`` to ``build_greeter`` /
``build_support`` to match the convention used by other multi-task
examples (e.g. ``build_sensor_controller``). They're public factories
the example exposes; the leading underscore was misleading.
Switch every example to ``await runner.spawn(task)`` followed by
``await runner.run()`` (no task argument), and ``await runner.cancel()``
on client-disconnected instead of ``await task.cancel()``. This makes
the main pipeline task look the same as the worker / proxy tasks
spawned alongside it, and lets ``runner.cancel()`` drive a uniform
shutdown across every root task on the bus.
Variant of the local handoff example with per-task TTS voices.
Each child task wraps the LLM with its own `CartesiaTTSService`
in a custom pipeline override, so the main task has no TTS and
audio comes from whichever child is active over the bus.
Two LLM tasks (greeter and support) handing off to each other over
the local `AsyncQueueBus`. The main task owns the transport
pipeline (STT, TTS, transport I/O) and the child tasks each run
their own LLM behind a `BusBridgeProcessor`. Each child uses
`bridged=()` so `PipelineTask` auto-wraps its pipeline with
the bus edge processors, and `transfer_to_agent` / `end_conversation`
tools demonstrate `handoff_to(...)` and `end(...)`.
