Enable configuration of the server bind address.

A serverconfig.env (or just environment variables) can be set to
override the default bind address/port for the backend. This is passed
to the front end as a query parameter.

game/server/settings.py

@@ -19,16 +19,15 @@ class ServerSettings(BaseSettings):
     # no client/server workflow yet, security has not been a focus.
     server_bind_address: str = "::1"
 
-    # If you for some reason change the port, you'll need to also update map.js and
-    # client/src/api/backend.ts.
+    # This (and the address) will be passed the the front end as a query parameter.
     server_port: int = 1688
 
-    # Disable to allow requests to be made to the backend without an API key.
-    require_api_key: bool = True
-
     # Enable to allow cross-origin requests from http://localhost:3000.
     cors_allow_debug_server: bool = False
 
+    class Config:
+        env_file = "serverconfig.env"
+
     @classmethod
     @lru_cache
     def get(cls) -> ServerSettings: