feat: allow use of full url for pwa manifest and icons

[tkint]

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Docs
• Underlying tools
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes
• No

Other information:

This PR allows use of pwa.manifestPath: 'https://other-domain.com/manifest.json' and makes more sense when using pwa.manifestCrossorigin: true.

I added support of full url for icons too, because it's the same way of building links.

[haoqunjiang]

Could you provide a practical use case for this feature, please?
I thought it makes more sense to provide a full URL for publicPath in this case.

[tkint]

Could you provide a practical use case for this feature, please?
I thought it makes more sense to provide a full URL for publicPath in this case.

If you do that, then all of your ressources must come from this same publicPath.

In my case, I want icons to be relative to the publicPath "/", but I want my manifest to come from a REST API with a full URL:

pwa: {
  name: 'My App',
  themeColor: '#FF6622',
  msTileColor: '#FF6622',
  favicon32: 'img/icons/favicon-32x32.png',
  manifestPath: 'https://my-api/getManifest',
  appleMobileWebAppCapable: 'yes',
  workboxOptions: {
    skipWaiting: true,
    clientsClaim: true,
    exclude: [/\.htaccess/],
  },
},

If I do that right now, I will get that in my index.html:

<link rel=manifest href=/https://my-api/getManifest>

And of course, the link is not valid.

[haoqunjiang]

Yeah that makes sense.

[vue-bot]

Hey @tkint, thank you for your time and effort spent on this PR, contributions like yours help make Vue better for everyone. Cheers! 💚