Add web interface for practice outside Discord

[tctree333]

Bird-ID has a web interface that allows you to practice ID without using Discord. According to analytics, the web interface is fairly popular, so I figure we should probably put more effort into the web versions.

SciOly-ID does not currently support a web interface. This issue will outline what I think needs to be done for it to happen.

• Optional but probably good to do: Migrate the existing Flask code (for image uploads) to FastAPI
• Reorganize file structure to be similar to Bird-ID
  • clear up ambiguities/conflicts between the practice API and uploads API
• Copy code from Bird-ID, generalize for non-bird usage (use config variables)
• Update the SciOly-ID website <- this is probably its own thing lmao

Contributions are welcome, so if you want to tackle one of these tasks or help out, please feel free to reach out! I will try to help you get things set up for development and answer any questions you may have.