Operators (and the new web UI) saw "No services registered" on every
vanilla boot because nothing in the boot sequence called
`ServiceRegistry::register()`. The Assist pipeline registers intent
handlers — a different surface — but `/api/services` stayed empty
until a plugin or integration loaded.
Adds `seed_default_services()` after `HomeCore::new()`. Each handler
is a `FnHandler` that echoes the call back as a JSON acknowledgement
so the service registry is exercise-able from day one. Integrations
override these by re-registering the same `ServiceName` with a real
handler later.
Seeded set:
homeassistant: restart, stop, reload_core_config
light: turn_on, turn_off, toggle
switch: turn_on, turn_off, toggle
scene: apply
automation: trigger
homecore: ping, snapshot_state (HOMECORE-native)
Boot log now reports:
Service registry seeded with 13 default service(s)
GET /api/services now returns 6 domains with 13 services total.
The HOMECORE web UI's Services page shows them under proper
domain headings.
Co-Authored-By: claude-flow <ruv@ruv.net>