feat: add registration page with captcha support

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/pages/register.vue

@@ -0,0 +1,137 @@
+<script setup lang="ts">
+import { z } from 'zod'
+
+const formSchema = z
+  .object({
+    username: z.string().trim().min(3, '用户名至少需要3个字符').max(30),
+    password: z.string().min(8, '密码至少需要8个字符'),
+    confirmPassword: z.string(),
+    captchaText: z.string().min(1, '请输入验证码'),
+  })
+  .refine((data) => data.password === data.confirmPassword, {
+    message: '两次输入的密码不一致',
+    path: ['confirmPassword'],
+  })
+
+const state = reactive({
+  username: '',
+  password: '',
+  confirmPassword: '',
+  captchaText: '',
+})
+
+const captchaToken = ref('')
+const captchaSvg = ref('')
+const loading = ref(false)
+const toast = useToast()
+
+async function fetchCaptcha() {
+  const res = await $fetch<{ code: number; data: { token: string; svg: string } }>(
+    '/api/auth/captcha'
+  )
+  captchaToken.value = res.data.token
+  captchaSvg.value = res.data.svg
+}
+
+async function onSubmit() {
+  loading.value = true
+  try {
+    const res = await $fetch<{ code: number; message: string; data: unknown }>(
+      '/api/auth/register',
+      {
+        method: 'POST',
+        body: {
+          username: state.username,
+          password: state.password,
+          confirmPassword: state.confirmPassword,
+          captchaToken: captchaToken.value,
+          captchaText: state.captchaText,
+        },
+      }
+    )
+
+    if (res.code !== 0) {
+      toast.add({ title: res.message, color: 'error' })
+      if (res.message.includes('验证码')) {
+        fetchCaptcha()
+        state.captchaText = ''
+      }
+      return
+    }
+
+    navigateTo('/login?registered=1')
+  } catch {
+    toast.add({ title: '注册失败，请稍后重试', color: 'error' })
+  } finally {
+    loading.value = false
+  }
+}
+
+onMounted(fetchCaptcha)
+</script>
+
+<template>
+  <div class="flex items-center justify-center py-8">
+    <UCard class="w-full max-w-[380px]">
+      <template #header>
+        <h1 class="text-xl font-semibold">Create Account</h1>
+        <p class="text-sm text-muted mt-1">Fill in the details to get started</p>
+      </template>
+
+      <UForm :state="state" :schema="formSchema" @submit="onSubmit">
+        <UFormField name="username" label="Username" required class="mb-4">
+          <UInput v-model="state.username" placeholder="Enter your username" />
+        </UFormField>
+
+        <UFormField name="password" label="Password" required class="mb-4">
+          <UInput
+            v-model="state.password"
+            type="password"
+            placeholder="At least 8 characters"
+          />
+        </UFormField>
+
+        <UFormField name="confirmPassword" label="Confirm Password" required class="mb-4">
+          <UInput
+            v-model="state.confirmPassword"
+            type="password"
+            placeholder="Re-enter your password"
+          />
+        </UFormField>
+
+        <UFormField name="captchaText" label="Captcha" required class="mb-4">
+          <div class="flex gap-2 items-start">
+            <!-- eslint-disable-next-line vue/no-v-html -->
+            <div
+              class="flex-1 h-10 border rounded-md overflow-hidden bg-[#f8f9fa]"
+              v-html="captchaSvg"
+            />
+            <UButton
+              variant="ghost"
+              color="neutral"
+              icon="i-lucide-refresh-cw"
+              square
+              @click="fetchCaptcha"
+            />
+          </div>
+          <UInput
+            v-model="state.captchaText"
+            placeholder="Enter the code above"
+            class="mt-2"
+          />
+        </UFormField>
+
+        <UButton type="submit" block :loading="loading" class="mt-6">
+          Create Account
+        </UButton>
+      </UForm>
+
+      <template #footer>
+        <p class="text-sm text-center text-muted">
+          Already have an account?
+          <NuxtLink to="/login" class="text-primary hover:underline">Log in</NuxtLink>
+        </p>
+      </template>
+    </UCard>
+  </div>
+</template>