feat: ios preprocessing page (url metadata)

[achorein]

Summary

on iOS we can use a JavaScript file to preprocess the webpage before the share extension is called (cf Accessing a Webpage). This is useful if we want to extract data directlty from the webpage and avoid to scrap the url in a second time.

Custom configuration example

    "plugins": [
      [
        "expo-share-intent",
        {
          "iosActivationRules": {
            "NSExtensionActivationSupportsWebURLWithMaxCount": 1,
            "NSExtensionActivationSupportsWebPageWithMaxCount": 1,
          },
          "preprocessorInjectJS": "metas['og\\:image'] = metas['og\\:image'] || document.querySelector('img#main-image')?.getAttribute('src')"
        }
      ],

Todo

• Add generic preprocessing script
• Auto extra all page header metadata (open graph) in share extension
• send all metadata to application
• add plugin configuration to add a custom rule to extract content
• Update README.md

Issue

Fixes #142

[ansh]

This would be an awesome feature to test!

[achorein]

@ansh now available ;)

[ansh]

You're an absolute legend.

Thank you!