chore(pwa): improve lighthouse pwa rating

[D-Nice]

• [ ] (grey) Content is sized correctly for the viewport
• [ ] (red) Is not configured for a custom splash screenFailures: Manifest does not have a PNG icon of at least 512px.
• [ ] (red) Does not provide fallback content when JavaScript is not availableThe page body should render some content if its scripts are not available.
• [ ] (red) Manifest doesn't have a maskable icon. A maskable icon ensures that the image fills the entire shape without being letterboxed when installing the app on a device.

Currently 5/8 score on lighthouse for PWA

While at it, also resolve Best Practices and SEO issues keeping them from being 100:

BP

• [ ] (red) Browser errors were logged to the console

  /workbox-3ec4d9f3.js(alpha.srspass.com) | no-response: no-response :: [{"url":"https://alpha.srspass.com/","error":{}}] at Object.handle (https://alpha.srspass.com/workbox-3ec4d9f3.js:1:10120)
  -- | --

SEO

• [ ] (red) Document does not have a meta description. Meta descriptions may be included in search results to concisely summarize page content. Learn more.