Server-side SEO

[chrismclarke]

PR Checklist

• [x] - Latest master branch merged
• [x] - PR title descriptive (can be used in release notes)

Description

@KingMike100 - follows on from #79, this time to add server-side dynamic updates for bots Proxies requests from bots to populate custom descriptions and images for problems, to make nice sharing cards

• add backend SEO functions
• update deploy scripts
• improve dynamic image generation
• improve meta tags and favicon

Git Issues

Closes #

Screenshots/Videos