API rate limiting 🔄 

### The issue ⚡ 

There is no API rate limiting implementation in place which puts the API endpoints at risk of abuse, i.e. DDOS.

### Suggested improvements 🔨 

Add rate limiting to protect the API endpoints against illegitimate use and abuse.

### References 🔗 

https://unkey.dev/docs/features/ratelimiting
https://github.com/upstash/ratelimit