style(settings): the Connections panel drops its two explainer paragraphs

Same cleanup as the General and DX Cluster panels: the section speaks for
itself, and the per-service hints remain where the choice is made.

frontend/src/components/SettingsModal.tsx

@@ -5716,10 +5716,7 @@ function SettingsModalImpl({ onClose, onSaved, initialSection, onMainPaneChanged
   function UDPIntegrationsPanelWrapper() {
     return (
       <>
-        <SectionHeader
-          title={t('sec.udp')}
-          hint={t('udp.hint')}
-        />
+        <SectionHeader title={t('sec.udp')} />
         <UDPIntegrationsPanel onError={(m) => setErr(m)} />
       </>
     );

frontend/src/components/UDPIntegrationsPanel.tsx

@@ -229,10 +229,6 @@ export function UDPIntegrationsPanel({ onError }: Props) {
 
   return (
     <div className="space-y-4">
-      <div className="text-[11px] text-muted-foreground max-w-2xl leading-relaxed">
-        {t('udpp.intro')}
-      </div>
-
       <Section
         title={t('udpp.inboundTitle')}
         icon={<ArrowDownToLine className="size-4" />}