added progressive web app (PWA) functionality to the site

[Tarek018]

I added Progressive Web App (PWA) functionality to the site ,
to test it, enter the following commands in the terminal:

• npm install --global http-server
• cd packages\site
• pnpm run build
• cd dist
• http-server
  So why do I add pwa?
  Sometimes I do offline development, so I need to see the components offline, so I added pwa to the site so that it can be accessed offline.

[Jesse205]

There are several issues that can be caused when a PWA is added

1. Update delay: When new content is available, PWA sites don't display new content immediately, but waits for all content to be cached before browsing the new content.
2. Can't continue to browse the old version of the page or Residual garbage: After the new cache is loaded, if the old cache is cleared, the user can no longer browse the old version of the page, and the user has to refresh to browse the new page.
3. Occupies additional storage resources. After visiting the PWA website, the website caches all the pages immediately. If a user only wants to browse one or two of these pages online, it is a waste for him.