fix: remove Better Auth useSession dependency from portal header

Replace client-side useSession hook with server-side prop passing.
Portal layout fetches user email server-side and passes to header.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/app/(portal)/layout.tsx

@@ -38,6 +38,7 @@ export default async function PortalLayout({
       <div className="flex-1 pl-64">
         <PortalHeader
           companyName={activeCompany?.display_name}
+          userEmail={session.user.email}
           isAdmin={isAdmin}
           unreadNotifications={unreadNotifications}
         />

src/components/layout/portal-header.tsx

@@ -2,7 +2,7 @@
 
 import { Bell, ChevronDown, LogOut, User } from 'lucide-react';
 import { useRouter } from 'next/navigation';
-import { signOut, useSession } from '@/lib/auth-client';
+import { signOut } from '@/lib/auth-client';
 import { Button } from '@/components/ui/button';
 import {
   DropdownMenu,
@@ -16,17 +16,18 @@ import { Badge } from '@/components/ui/badge';
 
 type PortalHeaderProps = {
   companyName?: string;
+  userEmail?: string;
   isAdmin?: boolean;
   unreadNotifications?: number;
 };
 
 export function PortalHeader({
   companyName,
+  userEmail,
   isAdmin,
   unreadNotifications = 0,
 }: PortalHeaderProps) {
   const router = useRouter();
-  const { data: session } = useSession();
 
   const handleSignOut = async () => {
     await signOut();
@@ -82,7 +83,7 @@ export function PortalHeader({
             <DropdownMenuTrigger asChild>
               <Button variant="ghost" className="flex items-center space-x-2">
                 <User className="h-5 w-5" />
-                <span className="hidden md:inline">{session?.user?.email}</span>
+                <span className="hidden md:inline">{userEmail}</span>
                 <ChevronDown className="h-4 w-4" />
               </Button>
             </DropdownMenuTrigger>