Restores v0.3.3 service manager capabilities:
- RegisterService(name, instance) stores the raw instance
- Auto-discovers Startable/Stoppable interfaces → wires lifecycle
- Auto-discovers HandleIPCEvents → wires to IPC bus
- ServiceFor[T](c, name) for typed instance retrieval
- Service DTO gains Instance field for instance tracking
WithService is a simple factory call — no reflect, no magic.
discoverHandlers removed — RegisterService handles it inline.
No double-registration: IPC wired once at registration time.
Co-Authored-By: Virgil <virgil@lethean.io>
Move source from go/core/ to root, tests from go/tests/ to tests/.
Module path dappco.re/go/core resolves cleanly — builds and tests pass.
Co-Authored-By: Virgil <virgil@lethean.io>