Remove the hosted rooms' old owner mapping

Hosted rooms' instance IDs start with their owner's IMVU account now, so the client asks about their
products as the owner itself, and the mapping from 2100000000 is never used.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

internal/products/products.go

@@ -73,10 +73,8 @@ type Products struct {
 	SaveDecorations func(ctx context.Context, instance string, items []DecorItem) error
 	decor           decorations
 
-	// Hosted, if set, serves T5DE-hosted rooms' queues (the hosted package); HostedOwner is the IMVU account owning
-	// the hosted room the client is in (0 if none), whose products the room's are.
-	Hosted      HostedRooms
-	HostedOwner func() int64
+	// Hosted, if set, serves T5DE-hosted rooms' queues (the hosted package).
+	Hosted HostedRooms
 
 	roomMu sync.Mutex
 	room   room
@@ -110,9 +108,8 @@ func (p *Products) Ready(id string) {
 	}
 }
 
-// HostedOwnerID is the user ID the client gives hosted rooms' owner: the first part of their instance IDs
-// (hosted.Base).
-const HostedOwnerID = 2100000000
+// hostedBase is where hosted rooms' numbers start (above it; hosted.Base).
+const hostedBase = 2100000000
 
 // HostedRooms serves T5DE-hosted rooms' IMQ queues: Route answers subscriptions to them, Send takes the client's
 // messages to them (message as for others, original as the client sent it, for the echo; keep: nothing to send