Secure Infura project key

Details: https://docs.infura.io/infura/networks/ethereum/how-to/secure-a-project

Patterns:

• Frontend/Mobile app:
  + Requests: 10/sec, 5000/day
  + Allowlists: Origins, Contract addresses, User agents (optional)
  + JWT required: Public (short expiration), Signed (long expiration)
• BE service:
  + Requests: x0/sec, x000/day
  + Allowlists: Contract addresses, User agents (optional)
  + Project secret required: JWT or API secret

Secure with API key secret