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>

database/migrations/2026_05_11_175856_create_reviews_table.php

@@ -0,0 +1,39 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::create('reviews', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('diving_offer_id')->constrained('diving_offers')->cascadeOnDelete();
+            $table->foreignId('member_id')->constrained('users')->cascadeOnDelete();
+            $table->tinyInteger('rating')->unsigned();
+            $table->text('comment');
+            $table->unsignedInteger('helpful_count')->default(0);
+            $table->boolean('is_edited')->default(false);
+            $table->timestamps();
+
+            $table->unique(['member_id', 'diving_offer_id']);
+            $table->index(['diving_offer_id', 'helpful_count'], 'idx_reviews_helpful');
+            $table->index(['diving_offer_id', 'rating'],        'idx_reviews_rating');
+            $table->index(['diving_offer_id', 'created_at'],   'idx_reviews_newest');
+            $table->index(['member_id', 'diving_offer_id'],    'idx_reviews_member_offer');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('reviews');
+    }
+};

database/migrations/2026_05_11_175857_create_review_edits_table.php

@@ -0,0 +1,30 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::create('review_edits', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('review_id')->unique()->constrained('reviews')->cascadeOnDelete();
+            $table->tinyInteger('old_rating')->unsigned();
+            $table->text('old_comment');
+            $table->timestamp('edited_at');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('review_edits');
+    }
+};

database/migrations/2026_05_11_175858_create_review_votes_table.php

@@ -0,0 +1,31 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        Schema::create('review_votes', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('review_id')->constrained('reviews')->cascadeOnDelete();
+            $table->foreignId('member_id')->constrained('users')->cascadeOnDelete();
+            $table->timestamp('created_at')->useCurrent();
+
+            $table->unique(['review_id', 'member_id']);
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::dropIfExists('review_votes');
+    }
+};