SEO optimizations

[franckc]

Issues with the highest impact on SEO ranking:

• Compress images to save 5.5s
  E.g: Header image reduced from 530KB to 168KB). We should use Next.js image optimization for all those. See
• https://www.originprotocol.com/robots.txt is still missing. It should be set to

User-Agent: *
Allow: /

• https://www.originprotocol.com/en isn't canonicalised to it's redirect target https://www.originprotocol.com/ so is throwing a duplicate page issue
• /tos and /privacy still have duplicate title tags and no meta description
• We also picked up +400 GA warnings re: orphan pages which seem to be part of the code base. e.g: https://www.originprotocol.com/_next/<xi:include href="http:/5ekxwup8jh1fvmdy43dmaiylpcv5j475v2it6i.oastify.com/foo"/>/AhUCwdhB0rQM4F5bCyX_K/_ssgManifest.js
• No support for HSTS

More detailed feedback in this doc.

[franckc]

@rolandpo When you have some cycles, could you take a look at those? Thank you!