feat: add user deletion functionality and fix known issues

app/Models/Coupon.php

@@ -24,17 +24,4 @@ class Coupon extends Model
         })->toArray();
     }
 
-    public function getLimitPlanIdsAttribute($value)
-    {
-        $planIds = json_decode($value, true);
-        
-        if (blank($planIds)) {
-            return null;
-        }
-        
-        return collect($planIds)
-            ->map(fn($id) => (string) $id)
-            ->values()
-            ->all();
-    }
 }

app/Models/User.php

@@ -42,6 +42,16 @@ class User extends Authenticatable
         return $this->hasMany(InviteCode::class, 'user_id', 'id');
     }
 
+    public function orders()
+    {
+        return $this->hasMany(Order::class, 'user_id', 'id');
+    }
+
+    public function stat()
+    {
+        return $this->hasMany(StatUser::class, 'user_id', 'id');
+    }
+
     // 关联工单列表
     public function tickets()
     {