refactor: 重构资产实体和DTO结构类型

将gjson.Json类型替换为具体的结构体和map类型，修正DAO层链式调用，启用SKU元数据校验逻辑

update.sql

@@ -123,4 +123,73 @@ COMMENT ON COLUMN assets_asset.virtual_asset_config IS '虚拟资产配置(JSONB
 COMMENT ON COLUMN assets_asset.metadata IS '动态元数据(JSONB)';
 COMMENT ON COLUMN assets_asset.tenant_module_type IS '租户模块类型';
 
---------------------pgsql创建assets_asset表语句---------------------------
+--------------------pgsql创建assets_asset表语句---------------------------
+
+--------------------pgsql创建assets_asset_sku表语句---------------------------
+-- 资产SKU表
+CREATE TABLE IF NOT EXISTS assets_asset_sku (
+    -- 基础字段（继承 SQLBaseDO 通用字段）
+                                                id BIGINT PRIMARY KEY, -- 主键ID（非自增）
+                                                creator VARCHAR(64) NOT NULL,
+    created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    updater VARCHAR(64) NOT NULL,
+    updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    deleted_at timestamp(6),
+
+    -- SKU核心字段
+    asset_id BIGINT NOT NULL, -- 关联资产ID
+    asset_name VARCHAR(128) NOT NULL, -- 资产名称
+    sku_name VARCHAR(128) NOT NULL, -- SKU名称
+    image_url VARCHAR(256) DEFAULT '', -- SKU主图
+    spec_values JSONB NOT NULL DEFAULT '[]'::JSONB, -- 规格值：{"颜色":"红色","尺寸":"L"}
+    price INT NOT NULL DEFAULT 0, -- 价格（分为单位）
+    unlimited_stock BOOLEAN NOT NULL DEFAULT FALSE, -- 是否无库存限制
+    stock INT NOT NULL DEFAULT 0, -- 库存数量
+    specs_count INT NOT NULL DEFAULT 0, -- 规格数量
+    specs_unit JSONB DEFAULT '{}'::JSONB, -- 规格单位 SpecsUnitKeyValue
+    sort INT NOT NULL DEFAULT 0, -- 排序
+    status SMALLINT NOT NULL DEFAULT 1, -- 资产状态：1启用/0停用
+    stock_mode SMALLINT NOT NULL DEFAULT 1, -- 库存管理模式：1-明细模式 2-批次模式
+    category_id BIGINT NOT NULL DEFAULT 0, -- 分类ID
+    category_path VARCHAR(512) DEFAULT '', -- 分类路径
+    tenant_module_type VARCHAR(32) DEFAULT '', -- 租户模块类型
+
+-- 外键约束（可选，根据业务需要启用）
+    CONSTRAINT fk_sku_asset_id FOREIGN KEY (asset_id) REFERENCES assets_asset(id) ON DELETE CASCADE,
+    CONSTRAINT fk_sku_category_id FOREIGN KEY (category_id) REFERENCES assets_category(id) ON DELETE SET DEFAULT
+    );
+
+-- 索引（根据查询场景优化）
+CREATE INDEX idx_sku_asset_id ON assets_asset_sku(asset_id);
+CREATE INDEX idx_sku_category_id ON assets_asset_sku(category_id);
+CREATE INDEX idx_sku_status ON assets_asset_sku(status);
+CREATE INDEX idx_sku_stock_mode ON assets_asset_sku(stock_mode);
+CREATE INDEX idx_sku_deleted_at ON assets_asset_sku(deleted_at); -- 软删字段索引
+CREATE INDEX idx_sku_tenant_module_type ON assets_asset_sku(tenant_module_type);
+
+-- 表和字段注释
+COMMENT ON TABLE assets_asset_sku IS '资产SKU表';
+COMMENT ON COLUMN assets_asset_sku.id IS '主键ID（非自增）';
+COMMENT ON COLUMN assets_asset_sku.creator IS '创建人';
+COMMENT ON COLUMN assets_asset_sku.created_at IS '创建时间';
+COMMENT ON COLUMN assets_asset_sku.updater IS '更新人';
+COMMENT ON COLUMN assets_asset_sku.updated_at IS '更新时间';
+COMMENT ON COLUMN assets_asset_sku.deleted_at IS '删除时间（软删）';
+COMMENT ON COLUMN assets_asset_sku.asset_id IS '关联资产ID';
+COMMENT ON COLUMN assets_asset_sku.asset_name IS '资产名称';
+COMMENT ON COLUMN assets_asset_sku.sku_name IS 'SKU名称';
+COMMENT ON COLUMN assets_asset_sku.image_url IS 'SKU主图';
+COMMENT ON COLUMN assets_asset_sku.spec_values IS '规格值：{"颜色":"红色","尺寸":"L","时长":"1个月","平台":"抖音"}';
+COMMENT ON COLUMN assets_asset_sku.price IS '价格（分为单位）';
+COMMENT ON COLUMN assets_asset_sku.unlimited_stock IS '是否无库存限制';
+COMMENT ON COLUMN assets_asset_sku.stock IS '库存数量';
+COMMENT ON COLUMN assets_asset_sku.specs_count IS '规格数量';
+COMMENT ON COLUMN assets_asset_sku.specs_unit IS '规格单位 SpecsUnitKeyValue';
+COMMENT ON COLUMN assets_asset_sku.sort IS '排序';
+COMMENT ON COLUMN assets_asset_sku.status IS '状态：active-启用/inactive-未启用/disabled-禁用';
+COMMENT ON COLUMN assets_asset_sku.stock_mode IS '库存管理模式：1-明细模式 2-批次模式';
+COMMENT ON COLUMN assets_asset_sku.category_id IS '分类ID';
+COMMENT ON COLUMN assets_asset_sku.category_path IS '分类路径';
+COMMENT ON COLUMN assets_asset_sku.tenant_module_type IS '租户模块类型';
+
+--------------------pgsql创建assets_sku表语句---------------------------