fix(contacts): name the Contacts sweep dir + light-skin badge contrast

Screenshot-sweep review follow-ups:
- sweepPageName() had its own page-name switch that lacked a Contacts case,
  so the tab's screenshots landed under the fallback "page/" dir. Add the
  case so they capture under "contacts/".
- The Z/T type badge (green/amber) washed out on light skins. Use darker,
  more-saturated variants when IsLightTheme(); keep the brighter ones on dark.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app_network.cpp

@@ -757,6 +757,7 @@ static const char* sweepPageName(ui::NavPage page)
         case ui::NavPage::Send:     return "send";
         case ui::NavPage::Receive:  return "receive";
         case ui::NavPage::History:  return "history";
+        case ui::NavPage::Contacts: return "contacts";
         case ui::NavPage::Mining:   return "mining";
         case ui::NavPage::Market:   return "market";
         case ui::NavPage::Console:  return "console";