bagisto_asset is a function which we made in shop package & it will not work in your package, asset is right function to use. We will update our doc & thanks for notifying us.
Make sure that you have run seeder command (php artisan db:seed) and you if see module development, there you can we need to create some configuration file for our package & add then accordingly to our core config files.
In this case, i think you have missed creating menu file and merging it to core files, so create a file in your packages config folder & marge this file to admin's menu file in your service provider.
dirname(DIR) . '/Config/yourfile.php', 'menu.admin'
your this file will consist name, key, route, icon & sort.
For more reference you can see our doc - https://devdocs.bagisto.com/.
I managed to solve the problem by duplicating the package.json from the 'packages/Webkul/Ui' package and run npm install and all the steps that karkiswapnil gave in his solution.
i recommend to not update packages but to use the same versions even if it warns you about vulnerability, otherwise you won't be able to follow the step by step of the documentation.
And please review your own 'package develop documentation, from the step 9 it starts to be a little confusing and redundant with the folder structure, you should upload the ideal folder structure for the helloworld package, thanks
core is facades and getConfigData() is a method inside this facades, getCofigData() is used to get data from configuration, first it check that if it exists in database ( which we save from configuration) then it will retrieve from there otherwise from configuration file. core facades is used to get core dependencies of project like currency, channel, locale & many more.
Please check out this guide once: https://bagisto.com/en/how-to-create-simple-product-in-bagisto/
Do let us know if you still face issue in displaying products in front-end.
Regarding products on sale, you can use the special price section or Promotion feature of bagisto which is added in the latest release. You can create cart rules and discount coupons for your customers.
@shreyasi if you want to create navigation menu then you have to override the following php file with your file :
follow the path :