The store's databases and query are registered under mesh-store, so the runtime serves them on the
seat's subjects wherever postgres holds the seat and never lists them as postgres's own; the claim
names them, so the mesh can judge the holder without postgres listing the seat's verbs among its
tools. Scoped to what the store enables: creating a database stays postgres's tool.
Named as the seat names them so the runtime finds them by name; the same calls as its own tools.
Its definition now lists its tools, which is what holding a seat with verbs demands at registration.
Merge before the controller declares the verbs on the mesh-store seat.