Carry an unassigned port as the declaration publishes it, refusing only a port a module does not listen on (issue 774, research 072 row 34)

influxdb and unifi publish bare ports that mesh-placement assigns none: the machine runs them at
the software's own number, so a plan refusing them held their whole plan for a route that works.

go/compose/rendering.go

@@ -245,13 +245,6 @@ func (c *composer) portsFor(node Node, plan catalogue.Resolution, settings catal
 					where = at
 				} else {
 					*foreseen = append(*foreseen, fmt.Sprintf("%s:%d", m.Module, l.Port))
-					if r.Unassigned == nil {
-						r.Unassigned = map[string]map[int]bool{}
-					}
-					if r.Unassigned[m.Module] == nil {
-						r.Unassigned[m.Module] = map[int]bool{}
-					}
-					r.Unassigned[m.Module][l.Port] = true
 				}
 			}
 			if ports[m.Module] == nil {