重构: 店铺套餐分配系统从加价模式改为返佣模式

主要变更：
- 重构分配模型：从加价模式（pricing_mode/pricing_value）改为返佣模式（base_commission + tier_commission）
- 删除独立的 my_package 接口，统一到 /api/admin/packages（通过数据权限自动过滤）
- 新增批量分配和批量调价功能，支持事务和性能优化
- 新增配置版本管理，订单创建时锁定返佣配置
- 新增成本价历史记录，支持审计和纠纷处理
- 新增统计缓存系统（Redis + 异步任务），优化梯度返佣计算性能
- 删除冗余的梯度佣金独立 CRUD 接口（合并到分配配置中）
- 归档 3 个已完成的 OpenSpec changes 并同步 8 个新 capabilities 到 main specs

技术细节：
- 数据库迁移：000026_refactor_shop_package_allocation
- 新增 Store：AllocationConfigStore, PriceHistoryStore, CommissionStatsStore
- 新增 Service：BatchAllocationService, BatchPricingService, CommissionStatsService
- 新增异步任务：统计更新、定时同步、周期归档
- 测试覆盖：批量操作集成测试、梯度佣金 CRUD 清理验证

影响：
- API 变更：删除 4 个梯度 CRUD 接口（POST/GET/PUT/DELETE /:id/tiers）
- API 新增：批量分配、批量调价接口
- 数据模型：重构 shop_series_allocation 表结构
- 性能优化：批量操作使用 CreateInBatches，统计使用 Redis 缓存

相关文档：
- openspec/changes/archive/2026-01-28-refactor-shop-package-allocation/
- openspec/specs/agent-available-packages/
- openspec/specs/allocation-config-versioning/
- 等 8 个新 capability specs

internal/store/postgres/package_store.go

@@ -7,6 +7,8 @@ import (
 
 	"github.com/break/junhong_cmp_fiber/internal/model"
 	"github.com/break/junhong_cmp_fiber/internal/store"
+	"github.com/break/junhong_cmp_fiber/pkg/constants"
+	"github.com/break/junhong_cmp_fiber/pkg/middleware"
 )
 
 type PackageStore struct {
@@ -51,20 +53,29 @@ func (s *PackageStore) List(ctx context.Context, opts *store.QueryOptions, filte
 
 	query := s.db.WithContext(ctx).Model(&model.Package{})
 
+	// 代理用户额外过滤：只能看到已分配的套餐
+	userType := middleware.GetUserTypeFromContext(ctx)
+	shopID := middleware.GetShopIDFromContext(ctx)
+	if userType == constants.UserTypeAgent && shopID > 0 {
+		query = query.Joins("INNER JOIN tb_shop_package_allocation ON tb_shop_package_allocation.package_id = tb_package.id").
+			Where("tb_shop_package_allocation.shop_id = ? AND tb_shop_package_allocation.status = ?",
+				shopID, constants.StatusEnabled)
+	}
+
 	if packageName, ok := filters["package_name"].(string); ok && packageName != "" {
-		query = query.Where("package_name LIKE ?", "%"+packageName+"%")
+		query = query.Where("tb_package.package_name LIKE ?", "%"+packageName+"%")
 	}
 	if seriesID, ok := filters["series_id"].(uint); ok && seriesID > 0 {
-		query = query.Where("series_id = ?", seriesID)
+		query = query.Where("tb_package.series_id = ?", seriesID)
 	}
 	if status, ok := filters["status"]; ok {
-		query = query.Where("status = ?", status)
+		query = query.Where("tb_package.status = ?", status)
 	}
 	if shelfStatus, ok := filters["shelf_status"]; ok {
-		query = query.Where("shelf_status = ?", shelfStatus)
+		query = query.Where("tb_package.shelf_status = ?", shelfStatus)
 	}
 	if packageType, ok := filters["package_type"].(string); ok && packageType != "" {
-		query = query.Where("package_type = ?", packageType)
+		query = query.Where("tb_package.package_type = ?", packageType)
 	}
 
 	if err := query.Count(&total).Error; err != nil {