refactor(forms): modernize random buttons in client + outbound modals

Replace the last holdouts of the old random-affordance patterns:
- ClientFormModal's five "↻" text buttons (email / subId / auth /
  password / uuid) now use <Button icon={<ReloadOutlined />} /> so
  they match the icon-based actions elsewhere in the form.
- OutboundFormModal's WireGuard private-key SyncOutlined-in-label
  becomes a real button inside a Space.Compact next to the key
  field — same pattern the inbound side already uses.

The shared .random-icon CSS class has no remaining consumers after
this and the previous inbound-form pass, so drop it from utils.css.

frontend/src/styles/utils.css

@@ -16,12 +16,6 @@
 
 .zero-margin { margin: 0; }
 
-.random-icon {
-  margin-left: 4px;
-  cursor: pointer;
-  color: var(--ant-color-primary);
-}
-
 .danger-icon {
   margin-left: 8px;
   cursor: pointer;