Auto priority when downloading content, loading zite

**Is your feature request related to a problem? Please describe.**

A simple setup could speed up the loading of content. If the user downloads a lot of data at once, the loading of the pages will slow down.

**Describe the solution you'd like**

-1 . When the user click a new content zite or file this point pause all another downloads untill the content download are finished then automatically contiune all other downloads. The point the program detect when the user currently want a content and when the user is less active the previously requested content the program downloads. So it doesn't matter how big the bandwidth is the content loading does not slow down.

-2. HTML, CSS, pictures, JS, PDF files are display the browser. Until these are downloaded, the website will not display properly. Always download this files first so zites are loading much faster. Then another files what does not need to display the website correctly can download the program when this files are finished.

-3. Download maximum 4 zite or large file and pause another files when the user not active. And when the 4 zite or large file are finished then contiune another downloads.

The issue names no files, tests, or entry points. Start by locating the existing download scheduling and zite-loading behavior, then define tests for pausing background downloads, prioritizing page assets, and limiting concurrent large downloads; done means the requested priority rules work without slowing page loading.

Do mô hình lập chỉ mục viết ra từ nội dung của issue.