feat:實作評價系統 — 匿名評價、有幫助投票、手動完成預約

後端：
- 新增 reviews / review_edits / review_votes migration（含索引）
- Review / ReviewEdit / ReviewVote Model
- ReviewController：評價 CRUD、資格驗證（completed booking）、rating 即時重算
- toggleHelpful：Member 限定、GREATEST 原子防負、DB transaction 同步
- AdminReviewController：全量列表、刪除（含重算）
- AdminBookingController：全量列表、手動標記 completed
- ProviderBookingController 新增 complete 方法（教練手動完成預約）
- DevelopmentSeeder：快速重建測試資料（admin/coach/member + offers + bookings）
- EnsureAdmin middleware 正式納入 bootstrap/app.php
- Nginx server_name 加入 cfdive.local

前端：
- 課程詳情頁加入評價區塊（星等分布、排序切換、撰寫/修改/刪除、有幫助 Toggle）
- Coach Portal 新增「課程評價」頁（只讀，依課程分組）
- Coach 預約管理加入「完成」按鈕
- Admin 新增「預約管理」頁（標記完成）、「評價管理」頁（刪除）
- Admin / Coach Navbar 新增對應連結

OpenSpec：
- review-system change 歸檔至 archive/2026-05-12-review-system
- 新增 specs/review-lifecycle 與 specs/review-voting 主規格
- review-voting spec 補充 Member 限定與 GREATEST 原子更新說明

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

frontend/src/views/coach/ReviewsView.vue

@@ -0,0 +1,101 @@
+<script setup>
+import { ref, onMounted } from 'vue'
+import coachApi from '../../api/coachAxios'
+import axios from 'axios'
+
+const publicApi = axios.create({
+  baseURL: import.meta.env.VITE_API_URL + '/api',
+  headers: { Accept: 'application/json' },
+})
+
+const offers   = ref([])
+const reviews  = ref([])   // [{ offer, reviews, summary }]
+const loading  = ref(true)
+
+onMounted(async () => {
+  try {
+    const offersRes = await coachApi.get('/provider/offers')
+    offers.value = offersRes.data.data
+
+    const results = await Promise.all(
+      offers.value.map(async (offer) => {
+        const res = await publicApi.get(`/diving-offers/${offer.id}/reviews`)
+        return { offer, ...res.data.data }
+      })
+    )
+    // 只顯示有評價的課程
+    reviews.value = results.filter(r => r.summary.total > 0)
+  } finally {
+    loading.value = false
+  }
+})
+
+function stars(n) {
+  return '★'.repeat(n) + '☆'.repeat(5 - n)
+}
+</script>
+
+<template>
+  <div class="p-6 max-w-4xl mx-auto">
+    <h1 class="text-2xl font-bold text-gray-800 mb-2">課程評價</h1>
+    <p class="text-sm text-gray-500 mb-6">學員對你課程的回饋（評價人已匿名）</p>
+
+    <div v-if="loading" class="text-center text-gray-400 py-20">載入中...</div>
+
+    <div v-else-if="reviews.length === 0" class="text-center text-gray-400 py-20">
+      目前沒有學員評價
+    </div>
+
+    <div v-else class="space-y-8">
+      <div v-for="group in reviews" :key="group.offer.id" class="bg-white rounded-2xl shadow p-6">
+
+        <!-- 課程標題與統計 -->
+        <div class="flex items-start justify-between mb-4 flex-wrap gap-3">
+          <div>
+            <h2 class="text-lg font-semibold text-gray-800">{{ group.offer.title }}</h2>
+            <p class="text-sm text-gray-500 mt-0.5">
+              ★ {{ group.summary.average }} · {{ group.summary.total }} 則評價
+            </p>
+          </div>
+          <!-- 評分分布 -->
+          <div class="space-y-0.5 min-w-[160px]">
+            <div v-for="star in [5,4,3,2,1]" :key="star" class="flex items-center gap-1.5 text-xs">
+              <span class="text-gray-400 w-4">{{ star }}★</span>
+              <div class="flex-1 bg-gray-100 rounded-full h-1.5">
+                <div class="bg-yellow-400 h-1.5 rounded-full"
+                  :style="`width:${group.summary.total > 0 ? (group.summary.distribution[star] / group.summary.total * 100) : 0}%`">
+                </div>
+              </div>
+              <span class="text-gray-400 w-3 text-right">{{ group.summary.distribution[star] }}</span>
+            </div>
+          </div>
+        </div>
+
+        <!-- 評價列表 -->
+        <div class="divide-y divide-gray-100">
+          <div v-for="r in group.reviews" :key="r.id" class="py-4 first:pt-0">
+            <div class="flex items-start gap-3">
+              <div class="w-8 h-8 rounded-full bg-ocean-100 flex items-center justify-center text-ocean-600 text-sm font-bold shrink-0">
+                匿
+              </div>
+              <div class="flex-1 min-w-0">
+                <div class="flex items-center gap-2 mb-1">
+                  <span class="text-yellow-400 text-sm">{{ stars(r.rating) }}</span>
+                  <span class="text-xs text-gray-400">{{ r.reviewer_name }}</span>
+                  <span v-if="r.is_edited" class="text-xs text-gray-400">（已修改）</span>
+                  <span class="text-xs text-gray-400 ml-auto">
+                    {{ new Date(r.created_at).toLocaleDateString('zh-TW') }}
+                  </span>
+                </div>
+                <p class="text-sm text-gray-700 leading-relaxed">{{ r.comment }}</p>
+                <p class="text-xs text-gray-400 mt-1.5">
+                  👍 {{ r.helpful_count }} 人覺得有幫助
+                </p>
+              </div>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  </div>
+</template>