Initial fullstack project setup with Next.js 15, Gin, PostgreSQL and Docker Compose

- Frontend: Next.js 15 (App Router), Auth.js v5, shadcn/ui, MagicUI
- Backend: Go + Gin + GORM with layered architecture
- Auth: Local credentials login with optional Keycloak OAuth binding
- Admin: RBAC user management for admin role
- Dev: Docker Compose with hot reload for both frontend and backend
- Docker: 3-service orchestration (frontend, backend, postgres)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/app/register/page.tsx

@@ -0,0 +1,113 @@
+"use client";
+
+import { useState } from "react";
+import { useRouter } from "next/navigation";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import { Label } from "@/components/ui/label";
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+
+export default function RegisterPage() {
+  const router = useRouter();
+  const [form, setForm] = useState({
+    username: "",
+    email: "",
+    password: "",
+    confirmPassword: "",
+  });
+  const [error, setError] = useState("");
+
+  async function handleSubmit(e: React.FormEvent) {
+    e.preventDefault();
+    setError("");
+
+    if (form.password !== form.confirmPassword) {
+      setError("两次输入的密码不一致");
+      return;
+    }
+
+    const res = await fetch("/api/proxy/auth/register", {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({
+        username: form.username,
+        email: form.email,
+        password: form.password,
+      }),
+    });
+
+    if (!res.ok) {
+      const data = await res.json();
+      setError(data.error || "注册失败");
+      return;
+    }
+
+    router.push("/login");
+  }
+
+  return (
+    <div className="flex min-h-screen items-center justify-center bg-gray-50 p-4">
+      <Card className="w-full max-w-md">
+        <CardHeader>
+          <CardTitle className="text-center">注册</CardTitle>
+        </CardHeader>
+        <CardContent className="space-y-4">
+          <form onSubmit={handleSubmit} className="space-y-4">
+            <div>
+              <Label htmlFor="username">用户名</Label>
+              <Input
+                id="username"
+                value={form.username}
+                onChange={(e) => setForm({ ...form, username: e.target.value })}
+                required
+              />
+            </div>
+            <div>
+              <Label htmlFor="email">邮箱</Label>
+              <Input
+                id="email"
+                type="email"
+                value={form.email}
+                onChange={(e) => setForm({ ...form, email: e.target.value })}
+                required
+              />
+            </div>
+            <div>
+              <Label htmlFor="password">密码</Label>
+              <Input
+                id="password"
+                type="password"
+                value={form.password}
+                onChange={(e) => setForm({ ...form, password: e.target.value })}
+                required
+              />
+            </div>
+            <div>
+              <Label htmlFor="confirmPassword">确认密码</Label>
+              <Input
+                id="confirmPassword"
+                type="password"
+                value={form.confirmPassword}
+                onChange={(e) =>
+                  setForm({ ...form, confirmPassword: e.target.value })
+                }
+                required
+              />
+            </div>
+            {error && <p className="text-sm text-red-500">{error}</p>}
+            <Button type="submit" className="w-full">
+              注册
+            </Button>
+          </form>
+
+          <p className="text-center text-sm text-gray-500">
+            已有账号？{" "}
+            <a href="/login" className="text-blue-600 hover:underline">
+              去登录
+            </a>
+          </p>
+        </CardContent>
+      </Card>
+    </div>
+  );
+}