Shopify API to add custom a section with long HTML code

I have an app that creates custom section on the active theme, but the file content is too long and I also added {% schema %}.
is there an option to upload a file as a section instead sending an array with endless code?

on the API documentation there is an option only for image URL but not for file/liquid URL for upload as section.

sample of PUT request i use:

PUT /admin/api/2021-01/themes/828155753/assets.json { “asset”: { “key”: “templates/index.liquid”, “value”: “

We are busy updating the store for you and will be back within the hour.

” } }

https://shopify.dev/docs/admin-api/rest/reference/online-store/asset

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