Add WIGOLO_SERVE_ALLOW_ORIGIN env var to skip Origin check on MCP transport

[UralterMann3]

What are you trying to do?

When running wigolo behind a web-based MCP client (e.g. AionUi), the client sends a browser Origin header. The hardcoded Origin rejection in mcpTransportRejected() blocks this, even with a valid bearer token.

What would you like wigolo to do?

Add an env var like WIGOLO_SERVE_ALLOW_ORIGIN=1 to skip the Origin check when a token is configured.

What do you do today instead?

nothing by now.

I will try nginx als proxy with manipulation
proxy_set_header Origin "";