Add basic API-key authentication on routes

[ff225]

Priority: Low

The APIs have no authentication: any device on the network can register and send data. Add a basic API-key check on the routes.

Tasks

• Require an API key (header) on the inference/registration routes
• Make the key configurable and documented

Files

• src/server/communication/http_server.py

From the Feature 042 codebase review (recommendation #16).