feat: 新增全局操作密码功能，将线下充值验证从登录密码改为统一操作密码

- 新增 RedisSystemOperationPasswordKey 常量函数（pkg/constants/redis.go）
- 新增 operation_password Service（Set/IsSet/Verify，bcrypt 哈希存 Redis）
- 新增 SuperAdminHandler 及两个接口：
  - POST /api/admin/super-admin/operation-password（设置/重置，仅超级管理员）
  - GET /api/admin/super-admin/operation-password/status（查询是否已设置）
- AgentRecharge.OfflinePay 操作密码验证从"查当前用户登录密码"改为"全局操作密码 Verify"
- Bootstrap/路由/文档生成器同步注册

internal/routes/admin.go

@@ -122,4 +122,7 @@ func RegisterAdminRoutes(router fiber.Router, handlers *bootstrap.Handlers, midd
 	if handlers.Refund != nil {
 		registerRefundRoutes(authGroup, handlers.Refund, doc, basePath)
 	}
+	if handlers.SuperAdmin != nil {
+		registerSuperAdminRoutes(authGroup, handlers.SuperAdmin, doc, basePath)
+	}
 }

internal/routes/super_admin.go

@@ -0,0 +1,28 @@
+package routes
+
+import (
+	"github.com/gofiber/fiber/v2"
+
+	"github.com/break/junhong_cmp_fiber/internal/handler/admin"
+	"github.com/break/junhong_cmp_fiber/internal/model/dto"
+	"github.com/break/junhong_cmp_fiber/pkg/openapi"
+)
+
+func registerSuperAdminRoutes(router fiber.Router, handler *admin.SuperAdminHandler, doc *openapi.Generator, basePath string) {
+	group := router.Group("/super-admin")
+	groupPath := basePath + "/super-admin"
+
+	Register(group, doc, groupPath, "POST", "/operation-password", handler.SetOperationPassword, RouteSpec{
+		Summary: "设置/修改全局操作密码",
+		Tags:    []string{"超级管理员"},
+		Input:   new(dto.SetOperationPasswordRequest),
+		Auth:    true,
+	})
+
+	Register(group, doc, groupPath, "GET", "/operation-password/status", handler.GetOperationPasswordStatus, RouteSpec{
+		Summary: "查询操作密码是否已设置",
+		Tags:    []string{"超级管理员"},
+		Output:  new(dto.OperationPasswordStatusResponse),
+		Auth:    true,
+	})
+}