Grant a provider only the consumers bound to it (hq issue 274)

grantsFor granted every consumer a pair credential from the provider was
ever made for, so a consumer pinned back to its own store was still asked
of the store it left, which then never retired it. A credential whose
consumer's resolution binds it elsewhere is now withdrawn like one nobody
asks for, kept on record for the login the provider keeps, and said on
plan and push.

internal/catalogue/declaration.go

@@ -174,6 +174,9 @@ type Rendering struct {
 	// bound (novox/hq ADR 0225). Composed into nothing; carried so the machine's declaration can say
 	// whom it does not serve, and why, beside what it does.
 	Withheld []Overflow
+	// Unbound is every consumer whose pair credential from this node is on record and whose own
+	// resolution binds it elsewhere (novox/hq issue 274): never granted, carried to be said.
+	Unbound []Unbound
 
 	// Ports is where this machine puts what each module needs reachable, by module and by the
 	// port the software itself uses (novox/hq ADR 0038).