The peer runtime used to spawn each long-running service inline inside
run_peer. That made the startup path harder to scan because service names,
clone setup, and task error handling were interleaved with the command loop.
Move the task wrappers into a startup module and leave run_peer as the
lifecycle overview: create shared context, start services, handle commands,
then send shutdown goodbyes. The spawned services and their error handling are
unchanged; only the ownership plumbing moved into named helpers.
Test Plan:
- cargo clippy
- cargo clippy --benches
- cargo clippy --tests
- cargo +nightly fmt
Refs: none
ddidderr
