feat(header): Display active S2A profile information in header

- Add Server icon import from lucide-react for profile display
- Import useConfig hook and S2AProfile type for configuration access
- Implement activeProfile state to track currently selected S2A profile
- Add useEffect hook to fetch and match S2A profiles against current API base configuration
- Replace spacer div with active profile information display component
- Show profile name and API base URL when profile is matched
- Display API base URL directly when configured but profile not found
- Add responsive styling with dark mode support for profile info badge
- Use truncation and flex-shrink to prevent layout overflow on smaller screens
- Provides users with clear visibility of which S2A profile is currently active

frontend/src/components/layout/Header.tsx

@@ -1,6 +1,8 @@
-import { Menu, Moon, Sun, Database, UserPlus } from 'lucide-react'
+import { Menu, Moon, Sun, Database, UserPlus, Server } from 'lucide-react'
 import { useState, useEffect } from 'react'
 import { useTeamStatus } from '../../hooks/useTeamStatus'
+import { useConfig } from '../../hooks/useConfig'
+import type { S2AProfile } from '../../types'
 
 interface HeaderProps {
   onMenuClick: () => void
@@ -10,6 +12,25 @@ interface HeaderProps {
 export default function Header({ onMenuClick, isConnected = false }: HeaderProps) {
   const [isDark, setIsDark] = useState(false)
   const teamStatus = useTeamStatus()
+  const { config } = useConfig()
+  const [activeProfile, setActiveProfile] = useState<S2AProfile | null>(null)
+
+  // 匹配当前活动配置对应的 profile 名称
+  useEffect(() => {
+    if (!config.s2a.apiBase) {
+      setActiveProfile(null)
+      return
+    }
+    fetch('/api/s2a/profiles')
+      .then(res => res.json())
+      .then(data => {
+        if (data.code === 0 && data.data) {
+          const match = (data.data as S2AProfile[]).find(p => p.api_base === config.s2a.apiBase)
+          setActiveProfile(match || null)
+        }
+      })
+      .catch(() => setActiveProfile(null))
+  }, [config.s2a.apiBase])
 
   useEffect(() => {
     // Check for saved theme preference or system preference
@@ -54,8 +75,21 @@ export default function Header({ onMenuClick, isConnected = false }: HeaderProps
         </span>
       </div>
 
-      {/* Spacer */}
+      {/* Active S2A Profile Info */}
-      <div className="flex-1" />
+      <div className="flex-1 flex items-center justify-start min-w-0">
+        {activeProfile ? (
+          <div className="flex items-center gap-2 min-w-0 px-2.5 py-1 rounded-lg bg-slate-50 dark:bg-slate-800/50 border border-slate-200/50 dark:border-slate-700/50">
+            <Server className="h-3.5 w-3.5 text-blue-500 flex-shrink-0" />
+            <span className="text-sm font-medium text-slate-700 dark:text-slate-300 truncate">{activeProfile.name}</span>
+            <span className="hidden md:inline text-xs text-slate-400 dark:text-slate-500 truncate">{activeProfile.api_base}</span>
+          </div>
+        ) : config.s2a.apiBase ? (
+          <div className="flex items-center gap-2 min-w-0 px-2.5 py-1 rounded-lg bg-slate-50 dark:bg-slate-800/50 border border-slate-200/50 dark:border-slate-700/50">
+            <Server className="h-3.5 w-3.5 text-slate-400 flex-shrink-0" />
+            <span className="hidden md:inline text-xs text-slate-400 dark:text-slate-500 truncate">{config.s2a.apiBase}</span>
+          </div>
+        ) : null}
+      </div>
 
       {/* Team Status Indicators */}
       {teamStatus.isProcessing && (