Checkpoint: v4.0 media service, compose deploy, and verified docs

client/src/pages/Dashboard.tsx

@@ -54,7 +54,7 @@ export default function Dashboard() {
       {/* Welcome header */}
       <div className="flex flex-col sm:flex-row sm:items-center sm:justify-between gap-4">
         <div>
-          <h1 className="text-2xl font-bold tracking-tight">
+          <h1 className="text-2xl font-bold tracking-tight" data-testid="dashboard-title">
             欢迎回来，{user?.name || "球友"}
           </h1>
           <div className="flex items-center gap-3 mt-2">
@@ -65,7 +65,7 @@ export default function Dashboard() {
           </div>
         </div>
         <div className="flex gap-2">
-          <Button onClick={() => setLocation("/training")} className="gap-2">
+          <Button data-testid="dashboard-training-button" onClick={() => setLocation("/training")} className="gap-2">
             <Target className="h-4 w-4" />
             开始训练
           </Button>