refactor: 一次性佣金配置从套餐级别提升到系列级别

主要变更:
- 新增 tb_shop_series_allocation 表，存储系列级别的一次性佣金配置
- ShopPackageAllocation 移除 one_time_commission_amount 字段
- PackageSeries 新增 enable_one_time_commission 字段控制是否启用一次性佣金
- 新增 /api/admin/shop-series-allocations CRUD 接口
- 佣金计算逻辑改为从 ShopSeriesAllocation 获取一次性佣金金额
- 删除废弃的 ShopSeriesOneTimeCommissionTier 模型
- OpenAPI Tag '系列分配' 和 '单套餐分配' 合并为 '套餐分配'

迁移脚本:
- 000042: 重构佣金套餐模型
- 000043: 简化佣金分配
- 000044: 一次性佣金分配重构
- 000045: PackageSeries 添加 enable_one_time_commission 字段

测试:
- 新增验收测试 (shop_series_allocation, commission_calculation)
- 新增流程测试 (one_time_commission_chain)
- 删除过时的单元测试（已被验收测试覆盖）

internal/model/dto/package_dto.go

@@ -2,18 +2,16 @@ package dto
 
 // CreatePackageRequest 创建套餐请求
 type CreatePackageRequest struct {
-	PackageCode          string  `json:"package_code" validate:"required,min=1,max=100" required:"true" minLength:"1" maxLength:"100" description:"套餐编码"`
-	PackageName          string  `json:"package_name" validate:"required,min=1,max=255" required:"true" minLength:"1" maxLength:"255" description:"套餐名称"`
-	SeriesID             *uint   `json:"series_id" validate:"omitempty" description:"套餐系列ID"`
-	PackageType          string  `json:"package_type" validate:"required,oneof=formal addon" required:"true" description:"套餐类型 (formal:正式套餐, addon:附加套餐)"`
-	DurationMonths       int     `json:"duration_months" validate:"required,min=1,max=120" required:"true" minimum:"1" maximum:"120" description:"套餐时长(月数)"`
-	DataType             *string `json:"data_type" validate:"omitempty,oneof=real virtual" description:"流量类型 (real:真流量, virtual:虚流量)"`
-	RealDataMB           *int64  `json:"real_data_mb" validate:"omitempty,min=0" minimum:"0" description:"真流量额度(MB)"`
-	VirtualDataMB        *int64  `json:"virtual_data_mb" validate:"omitempty,min=0" minimum:"0" description:"虚流量额度(MB)"`
-	DataAmountMB         *int64  `json:"data_amount_mb" validate:"omitempty,min=0" minimum:"0" description:"总流量额度(MB)"`
-	Price                int64   `json:"price" validate:"required,min=0" required:"true" minimum:"0" description:"套餐价格(分)"`
-	SuggestedCostPrice   *int64  `json:"suggested_cost_price" validate:"omitempty,min=0" minimum:"0" description:"建议成本价(分)"`
-	SuggestedRetailPrice *int64  `json:"suggested_retail_price" validate:"omitempty,min=0" minimum:"0" description:"建议售价(分)"`
+	PackageCode          string `json:"package_code" validate:"required,min=1,max=100" required:"true" minLength:"1" maxLength:"100" description:"套餐编码"`
+	PackageName          string `json:"package_name" validate:"required,min=1,max=255" required:"true" minLength:"1" maxLength:"255" description:"套餐名称"`
+	SeriesID             *uint  `json:"series_id" validate:"omitempty" description:"套餐系列ID"`
+	PackageType          string `json:"package_type" validate:"required,oneof=formal addon" required:"true" description:"套餐类型 (formal:正式套餐, addon:附加套餐)"`
+	DurationMonths       int    `json:"duration_months" validate:"required,min=1,max=120" required:"true" minimum:"1" maximum:"120" description:"套餐时长(月数)"`
+	RealDataMB           *int64 `json:"real_data_mb" validate:"omitempty,min=0" minimum:"0" description:"真流量额度(MB)"`
+	VirtualDataMB        *int64 `json:"virtual_data_mb" validate:"omitempty,min=0" minimum:"0" description:"虚流量额度(MB)"`
+	EnableVirtualData    bool   `json:"enable_virtual_data" description:"是否启用虚流量"`
+	SuggestedRetailPrice *int64 `json:"suggested_retail_price" validate:"omitempty,min=0" minimum:"0" description:"建议售价(分)"`
+	CostPrice            int64  `json:"cost_price" validate:"required,min=0" required:"true" minimum:"0" description:"成本价(分)"`
 }
 
 // UpdatePackageRequest 更新套餐请求
@@ -22,13 +20,11 @@ type UpdatePackageRequest struct {
 	SeriesID             *uint   `json:"series_id" validate:"omitempty" description:"套餐系列ID"`
 	PackageType          *string `json:"package_type" validate:"omitempty,oneof=formal addon" description:"套餐类型 (formal:正式套餐, addon:附加套餐)"`
 	DurationMonths       *int    `json:"duration_months" validate:"omitempty,min=1,max=120" minimum:"1" maximum:"120" description:"套餐时长(月数)"`
-	DataType             *string `json:"data_type" validate:"omitempty,oneof=real virtual" description:"流量类型 (real:真流量, virtual:虚流量)"`
 	RealDataMB           *int64  `json:"real_data_mb" validate:"omitempty,min=0" minimum:"0" description:"真流量额度(MB)"`
 	VirtualDataMB        *int64  `json:"virtual_data_mb" validate:"omitempty,min=0" minimum:"0" description:"虚流量额度(MB)"`
-	DataAmountMB         *int64  `json:"data_amount_mb" validate:"omitempty,min=0" minimum:"0" description:"总流量额度(MB)"`
-	Price                *int64  `json:"price" validate:"omitempty,min=0" minimum:"0" description:"套餐价格(分)"`
-	SuggestedCostPrice   *int64  `json:"suggested_cost_price" validate:"omitempty,min=0" minimum:"0" description:"建议成本价(分)"`
+	EnableVirtualData    *bool   `json:"enable_virtual_data" description:"是否启用虚流量"`
 	SuggestedRetailPrice *int64  `json:"suggested_retail_price" validate:"omitempty,min=0" minimum:"0" description:"建议售价(分)"`
+	CostPrice            *int64  `json:"cost_price" validate:"omitempty,min=0" minimum:"0" description:"成本价(分)"`
 }
 
 // PackageListRequest 套餐列表请求
@@ -61,28 +57,26 @@ type CommissionTierInfo struct {
 
 // PackageResponse 套餐响应
 type PackageResponse struct {
-	ID                    uint                `json:"id" description:"套餐ID"`
-	PackageCode           string              `json:"package_code" description:"套餐编码"`
-	PackageName           string              `json:"package_name" description:"套餐名称"`
-	SeriesID              *uint               `json:"series_id" description:"套餐系列ID"`
-	SeriesName            *string             `json:"series_name" description:"套餐系列名称"`
-	PackageType           string              `json:"package_type" description:"套餐类型 (formal:正式套餐, addon:附加套餐)"`
-	DurationMonths        int                 `json:"duration_months" description:"套餐时长(月数)"`
-	DataType              string              `json:"data_type" description:"流量类型 (real:真流量, virtual:虚流量)"`
-	RealDataMB            int64               `json:"real_data_mb" description:"真流量额度(MB)"`
-	VirtualDataMB         int64               `json:"virtual_data_mb" description:"虚流量额度(MB)"`
-	DataAmountMB          int64               `json:"data_amount_mb" description:"总流量额度(MB)"`
-	Price                 int64               `json:"price" description:"套餐价格(分)"`
-	SuggestedCostPrice    int64               `json:"suggested_cost_price" description:"建议成本价(分)"`
-	SuggestedRetailPrice  int64               `json:"suggested_retail_price" description:"建议售价(分)"`
-	Status                int                 `json:"status" description:"状态 (1:启用, 2:禁用)"`
-	ShelfStatus           int                 `json:"shelf_status" description:"上架状态 (1:上架, 2:下架)"`
-	CreatedAt             string              `json:"created_at" description:"创建时间"`
-	UpdatedAt             string              `json:"updated_at" description:"更新时间"`
-	CostPrice             *int64              `json:"cost_price,omitempty" description:"成本价（分，仅代理用户可见）"`
-	ProfitMargin          *int64              `json:"profit_margin,omitempty" description:"利润空间（分，仅代理用户可见）"`
-	CurrentCommissionRate string              `json:"current_commission_rate,omitempty" description:"当前返佣比例（仅代理用户可见）"`
-	TierInfo              *CommissionTierInfo `json:"tier_info,omitempty" description:"梯度返佣信息（仅代理用户可见）"`
+	ID                      uint                `json:"id" description:"套餐ID"`
+	PackageCode             string              `json:"package_code" description:"套餐编码"`
+	PackageName             string              `json:"package_name" description:"套餐名称"`
+	SeriesID                *uint               `json:"series_id" description:"套餐系列ID"`
+	SeriesName              *string             `json:"series_name" description:"套餐系列名称"`
+	PackageType             string              `json:"package_type" description:"套餐类型 (formal:正式套餐, addon:附加套餐)"`
+	DurationMonths          int                 `json:"duration_months" description:"套餐时长(月数)"`
+	RealDataMB              int64               `json:"real_data_mb" description:"真流量额度(MB)"`
+	VirtualDataMB           int64               `json:"virtual_data_mb" description:"虚流量额度(MB)"`
+	EnableVirtualData       bool                `json:"enable_virtual_data" description:"是否启用虚流量"`
+	SuggestedRetailPrice    int64               `json:"suggested_retail_price" description:"建议售价(分)"`
+	CostPrice               int64               `json:"cost_price" description:"成本价(分)"`
+	OneTimeCommissionAmount *int64              `json:"one_time_commission_amount,omitempty" description:"一次性佣金金额（分，代理视角）"`
+	Status                  int                 `json:"status" description:"状态 (1:启用, 2:禁用)"`
+	ShelfStatus             int                 `json:"shelf_status" description:"上架状态 (1:上架, 2:下架)"`
+	CreatedAt               string              `json:"created_at" description:"创建时间"`
+	UpdatedAt               string              `json:"updated_at" description:"更新时间"`
+	ProfitMargin            *int64              `json:"profit_margin,omitempty" description:"利润空间（分，仅代理用户可见）"`
+	CurrentCommissionRate   string              `json:"current_commission_rate,omitempty" description:"当前返佣比例（仅代理用户可见）"`
+	TierInfo                *CommissionTierInfo `json:"tier_info,omitempty" description:"梯度返佣信息（仅代理用户可见）"`
 }
 
 // UpdatePackageParams 更新套餐聚合参数