add social media preview (twitter, facebook, ...)

[serapath]

@todo

• when somebody pastes a link to our page on twitter or facebook or somewhere, we need to show a preview
• check:
  • https://developers.facebook.com/tools/debug/sharing/?q=https%3A%2F%2Fsmartcontract.codes
  • https://stackoverflow.com/a/26537086
• use maybe:
  • http://www.page2images.com/
  • to get something like: http://api.page2images.com/ccimages/b6/f8/n6ckdxRiD0E7rQOP.png
• research twitter card options
• research facebook card options
• research others (e.g. instagram, tiktok?, snapchat?, ...)
• make concept for preview card for different play apps
• implement facebook card
• implement twitter card

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reading materials:

• check result https://cards-dev.twitter.com/validator
• check result https://developers.facebook.com/tools/debug/og/object/
• https://developer.twitter.com/en/docs/tweets/optimize-with-cards/guides/getting-started
• https://developers.facebook.com/docs/sharing/webmasters
• more https://sproutsocial.com/insights/twitter-cards-guide/
• old https://davidwalsh.name/twitter-cards