The daemon drains the library's destructive take_* accessors once and fans
events out per connection, which is what lets more than one client share a
session. A Unix socket at 0600 is the local transport and its permissions
are the authentication; TCP is opt-in and needs the generated token. Rooms,
transfers, and the conversation are daemon-owned and restored on restart.
Methods and events are enums built by one macro, so every consumer matches
exhaustively: adding a member is a compile error until the dispatcher, the
published schema, and the remote client all handle it. docs/openrpc.json is
derived from the DTOs rather than hand-written, and a test fails the build
when the checked-in copy drifts.