Rust rewrite

[Douile]

Rewrite entire bot in rust using the serenity library for much improved resource efficiency.

This will involve some re-architecture.

• The bot client will no longer connect to the scheduler: status updates now exclusively use HTTP API endpoints meaning they do not need an active gateway connection.
  • A seperate updater program will run that connects to scheduler and just sends updates
  • This program will be built with sharding in mind, hence need to add way to easily distribute bot configuration between them (rewrite scheduler protocol)
  • Possibly swap out JSON for more efficient machine parsable format
  • Possibly add TLS support for scheduler
  • This depends on https://github.com/gamedig/rust-gamedig to be ready (it mostly is)
• Bot client will be reduced to most basic functionality: recieve slash command, update database, generate message.
  • Database updates will be optimised by creating specific queries for each specific use case instead of updating each status as its own unit.
  • Hopefully take advantage of new discord features like buttons and modals
• Database changes
  • db is central point of reference for all components therefore it might be the best place to store the bot configuration
  • statuses table could be optimised, better indexes, remove data for functionality thats not really used
    • player change list (stores entire response json)
    • last server title (stores entire response json)
  • if changing database schema should add unit tests to confirm that migration will work

Other tasks

• create a component diagram of this architecture
• get docs up to scratch, especially for slash commands as regular commands are being removed
• support internationalization out the gate
• performance metrics so benefit of rewrite can be measured