fix: update user fields to match schema

- Replace firstName/lastName with name field in users API route
- Update user formatting in UsersTab component
- Add email fallback when name is not available

src/app/dashboard/page.tsx

@@ -4,19 +4,18 @@ import { useEffect, useState } from "react";
 import { useRouter } from "next/navigation";
 import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "~/components/ui/card";
 import { Button } from "~/components/ui/button";
-import { Users, BookOpen, Settings2 } from "lucide-react";
+import { BookOpen, Settings2 } from "lucide-react";
 import { useToast } from "~/hooks/use-toast";
+import { Breadcrumb } from "~/components/breadcrumb";
 
 interface DashboardStats {
   studyCount: number;
-  participantCount: number;
   activeInvitationCount: number;
 }
 
 export default function Dashboard() {
   const [stats, setStats] = useState<DashboardStats>({
     studyCount: 0,
-    participantCount: 0,
     activeInvitationCount: 0,
   });
   const [loading, setLoading] = useState(true);
@@ -34,8 +33,7 @@ export default function Dashboard() {
       
       // For now, just show study count
       setStats({
-        studyCount: studies.length,
-        participantCount: 0,
+        studyCount: studies.data.length,
         activeInvitationCount: 0,
       });
     } catch (error) {
@@ -59,35 +57,26 @@ export default function Dashboard() {
   }
 
   return (
-    <div className="container py-6 space-y-6">
+    <div className="space-y-6">
+      <Breadcrumb />
+      
       <div>
         <h1 className="text-2xl font-bold">Dashboard</h1>
         <p className="text-muted-foreground">Overview of your research studies</p>
       </div>
 
-      <div className="grid gap-4 md:grid-cols-3">
+      <div className="grid gap-4 md:grid-cols-2">
         <Card>
           <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
             <CardTitle className="text-sm font-medium">Total Studies</CardTitle>
             <BookOpen className="h-4 w-4 text-muted-foreground" />
           </CardHeader>
           <CardContent>
-            <div className="text-2xl font-bold">{stats.studyCount ? stats.studyCount : 0}</div>
+            <div className="text-2xl font-bold">{stats.studyCount}</div>
             <p className="text-xs text-muted-foreground">Active research studies</p>
           </CardContent>
         </Card>
 
-        <Card>
-          <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
-            <CardTitle className="text-sm font-medium">Total Participants</CardTitle>
-            <Users className="h-4 w-4 text-muted-foreground" />
-          </CardHeader>
-          <CardContent>
-            <div className="text-2xl font-bold">{stats.participantCount}</div>
-            <p className="text-xs text-muted-foreground">Across all studies</p>
-          </CardContent>
-        </Card>
-
         <Card>
           <CardHeader className="flex flex-row items-center justify-between space-y-0 pb-2">
             <CardTitle className="text-sm font-medium">Pending Invitations</CardTitle>
@@ -115,14 +104,6 @@ export default function Dashboard() {
               <BookOpen className="mr-2 h-4 w-4" />
               Manage Studies
             </Button>
-            <Button
-              variant="outline"
-              className="w-full justify-start"
-              onClick={() => router.push('/dashboard/participants')}
-            >
-              <Users className="mr-2 h-4 w-4" />
-              Manage Participants
-            </Button>
           </CardContent>
         </Card>
 
@@ -139,7 +120,7 @@ export default function Dashboard() {
               • Invite collaborators using study settings
             </p>
             <p className="text-sm text-muted-foreground">
-              • Add participants to begin collecting data
+              • Configure study parameters and forms
             </p>
           </CardContent>
         </Card>