message: refactor(docs-infra): more some `pwa-manifest.json` keys to the top to improve readability
  This commit moves some properties with simple, string values in
  `pwa-manifest.json` to the top (i.e. above the more lengthy `icons`
  array) to make them easier to discover.
  PR Close
diff: {
  - "short_name": "angular.io",
  "name": "Angular Documentation",
  + "short_name": "angular.io",
  + "background_color": "#1976d2",
  + "theme_color": "#1976d2",
  + "display": "standalone",
  "icons": [
  {
  "src": "assets/images/favicons/favicon-194x194.png",
  "purpose": "maskable"
  }
  ],
  - "start_url": "/?utm_source=homescreen",
  - "background_color": "#1976d2",
  - "theme_color": "#1976d2",
  - "display": "standalone"
  + "start_url": "/?utm_source=homescreen"
  }
  