Give the uplink seat its verbs, staged until its holders serve them (hq ADR 0241)

What a machine resolves through and over which links had no tool: the
resolver file and its writer, and each link with its routes and resolvers,
are now verbs of node-uplink, the same whatever manages the network. A verb
required at once would refuse every holder before the catalogue could serve
it, and a stored one would be required by an older controller, so it is
staged: promised and routed, never stored, and not yet a condition of
holding.

internal/inventory/seats.go

@@ -62,6 +62,8 @@ func (i *Inventory) Seats(ctx context.Context) ([]catalogue.Seat, error) {
 func (i *Inventory) SeedSeats(ctx context.Context, defaults []catalogue.Seat) (int, error) {
 	var added int
 	for _, s := range defaults {
+		// A verb still staged is never stored (catalogue.Seat.Staged).
+		s = s.Stored()
 		accepts, emits, serves, err := protocolJSON(s)
 		if err != nil {
 			return added, err