feat:實作 Member Portal MVP 前端與後端整合

後端：
- 新增 DivingOffer Model / DivingOfferController（列表+詳情 API，支援搜尋/篩選/分頁）
- 修正 Google OAuth callback 改為 redirect 至前端（SocialAuthController）
- 新增 config/cors.php 允許前端 origin
- .gitignore 新增 frontend/ 排除規則

前端（frontend/）：
- Vue 3 + Vite + Tailwind CSS + Pinia + Vue Router
- 頁面：首頁、課程列表、課程詳情、登入、註冊、個人資料、OAuth callback
- 整合至 Docker（multi-stage build，nginx 靜態服務於 port 5173）

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>

frontend/src/views/LoginView.vue

@@ -0,0 +1,110 @@
+<script setup>
+import { ref } from 'vue'
+import { useRouter, useRoute } from 'vue-router'
+import api from '../api/axios'
+import { useAuthStore } from '../stores/auth'
+
+const router = useRouter()
+const route  = useRoute()
+const auth   = useAuthStore()
+
+const email    = ref('')
+const password = ref('')
+const error    = ref('')
+const loading  = ref(false)
+
+const oauthError = route.query.error === 'oauth_failed'
+  ? 'Google 登入失敗，請重試。'
+  : ''
+
+const successMsg = route.query.registered ? '註冊成功，請登入。' : ''
+
+async function submit() {
+  error.value   = ''
+  loading.value = true
+  try {
+    const res = await api.post('/member/login', {
+      email:    email.value,
+      password: password.value,
+    })
+    auth.setAuth(res.data.data.user, res.data.data.token)
+    router.push('/courses')
+  } catch (e) {
+    error.value = e.response?.data?.message || '帳號或密碼錯誤'
+  } finally {
+    loading.value = false
+  }
+}
+
+function loginWithGoogle() {
+  window.location.href = import.meta.env.VITE_API_URL + '/api/auth/google/redirect'
+}
+</script>
+
+<template>
+  <main class="min-h-[80vh] flex items-center justify-center px-4">
+    <div class="bg-white rounded-2xl shadow-lg w-full max-w-md p-8">
+      <h1 class="text-2xl font-bold text-gray-800 mb-6 text-center">會員登入</h1>
+
+      <div v-if="successMsg" class="bg-green-50 text-green-700 text-sm rounded-lg px-4 py-3 mb-4">
+        {{ successMsg }}
+      </div>
+      <div v-if="oauthError || error" class="bg-red-50 text-red-600 text-sm rounded-lg px-4 py-3 mb-4">
+        {{ oauthError || error }}
+      </div>
+
+      <form @submit.prevent="submit" class="flex flex-col gap-4">
+        <div>
+          <label class="block text-sm text-gray-600 mb-1">Email</label>
+          <input
+            v-model="email"
+            type="email"
+            required
+            class="w-full border border-gray-300 rounded-lg px-4 py-2 focus:outline-none focus:ring-2 focus:ring-ocean-400"
+          />
+        </div>
+        <div>
+          <label class="block text-sm text-gray-600 mb-1">密碼</label>
+          <input
+            v-model="password"
+            type="password"
+            required
+            class="w-full border border-gray-300 rounded-lg px-4 py-2 focus:outline-none focus:ring-2 focus:ring-ocean-400"
+          />
+        </div>
+
+        <button
+          type="submit"
+          :disabled="loading"
+          class="bg-ocean-700 hover:bg-ocean-600 text-white font-semibold py-2.5 rounded-lg transition disabled:opacity-60"
+        >
+          {{ loading ? '登入中...' : '登入' }}
+        </button>
+      </form>
+
+      <div class="relative my-5 flex items-center">
+        <div class="flex-1 border-t border-gray-200"></div>
+        <span class="mx-3 text-sm text-gray-400">或</span>
+        <div class="flex-1 border-t border-gray-200"></div>
+      </div>
+
+      <button
+        @click="loginWithGoogle"
+        class="w-full flex items-center justify-center gap-3 border border-gray-300 rounded-lg py-2.5 hover:bg-gray-50 transition text-sm font-medium text-gray-700"
+      >
+        <svg class="w-5 h-5" viewBox="0 0 48 48">
+          <path fill="#EA4335" d="M24 9.5c3.5 0 6.6 1.2 9 3.2l6.7-6.7C35.8 2.5 30.2 0 24 0 14.6 0 6.6 5.4 2.5 13.3l7.8 6C12.3 13.1 17.7 9.5 24 9.5z"/>
+          <path fill="#4285F4" d="M46.5 24.5c0-1.6-.1-3.2-.4-4.7H24v9h12.7c-.6 3-2.3 5.5-4.8 7.2l7.6 5.9C43.8 37.6 46.5 31.5 46.5 24.5z"/>
+          <path fill="#FBBC05" d="M10.3 28.7A14.7 14.7 0 0 1 9.5 24c0-1.6.3-3.2.8-4.7l-7.8-6A23.9 23.9 0 0 0 0 24c0 3.9.9 7.5 2.5 10.7l7.8-6z"/>
+          <path fill="#34A853" d="M24 48c6.2 0 11.4-2 15.2-5.5l-7.6-5.9c-2 1.4-4.7 2.2-7.6 2.2-6.3 0-11.7-3.6-13.7-9.1l-7.8 6C6.6 42.6 14.6 48 24 48z"/>
+        </svg>
+        以 Google 帳號登入
+      </button>
+
+      <p class="text-center text-sm text-gray-500 mt-6">
+        還沒有帳號？
+        <RouterLink to="/register" class="text-ocean-600 hover:underline">立即註冊</RouterLink>
+      </p>
+    </div>
+  </main>
+</template>