One-view tokens: local records in linked zones, zone lookup, view list

A token for one view of a linked zone (an ACME token for external)
couldn't add records: a new record was shared and reached the other
view. A new name and type is now local when the user may not change it
in the other views. A zone name in several views resolves to the only
one the user can see, and the error no longer names views they can't.
GET /views lists the views a user sees zones in (name, colour, count;
limited) without views:read.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/server/h_config.go

@@ -57,6 +57,8 @@ func (s *Server) listViews(w http.ResponseWriter, r *http.Request, p *auth.Princ
 	for _, v := range st.OrderedViews() {
 		if p.Can(auth.Action{Resource: auth.ResViews, View: v.Name}) {
 			out = append(out, presentView(st, v, colors))
+		} else if lv := limitedView(st, v, colors, p); lv != nil {
+			out = append(out, *lv)
 		}
 	}
 	writeJSON(w, http.StatusOK, out)