chore: 清除廢棄的 DB 表與 Model

- 新增 migration 刪除 coach_profiles、coach_member、plans、subscriptions 四張廢棄表
- 刪除對應的空殼 Model：CoachProfile、Plan、Subscription

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

app/Models/CoachProfile.php

@@ -1,32 +0,0 @@
-<?php
-
-namespace App\Models;
-
-use Illuminate\Database\Eloquent\Model;
-
-// 該模型已棄用，請使用ProviderProfile模型
-class CoachProfile extends Model
-{
-    /**
-     * 可以批量分配的屬性
-     *
-     * @var array<int, string>
-     */
-    protected $fillable = [
-        'user_id',
-        'bio',
-        'expertise',
-        'certification',
-        'experience',
-        'rating',
-        'availability'
-    ];
-
-    /**
-     * 與用戶的關聯
-     */
-    public function user()
-    {
-        return $this->belongsTo(User::class);
-    }
-}

app/Models/Plan.php

@@ -1,10 +0,0 @@
-<?php
-
-namespace App\Models;
-
-use Illuminate\Database\Eloquent\Model;
-
-class Plan extends Model
-{
-    //
-}

app/Models/Subscription.php

@@ -1,10 +0,0 @@
-<?php
-
-namespace App\Models;
-
-use Illuminate\Database\Eloquent\Model;
-
-class Subscription extends Model
-{
-    //
-}

database/migrations/2026_05_25_083147_drop_unused_tables.php

@@ -0,0 +1,20 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::dropIfExists('subscriptions');
+        Schema::dropIfExists('plans');
+        Schema::dropIfExists('coach_member');
+        Schema::dropIfExists('coach_profiles');
+    }
+
+    public function down(): void
+    {
+        // 這些表已確認廢棄，不提供還原
+    }
+};