Support HTTP in unity_connection

[lewis-v]

Why is the connection with Unity chosen to use socket instead of directly using http? I see that the connection here is also sending and waiting for the return packet each time, and there is no special reliance on long connections.

[msanatan]

@justinpbarnett probably has the most historical context

[justinpbarnett]

Honestly wasn't a huge reason, just a choice made in the moment. TCP sockets have lower latency, plus MCP uses a stdio design and it's similar so I don't have to context switch as hard.

[Sfsx]

When the Unity Editor is reloaded, the TCP connection is interrupted and needs to be re-established after recovery. During this period, any TCP request will fail. If it is a stateless HTTP, this is not necessary. The other party only needs to wait during the reload and send the message when everything is ready.

[msanatan]

Good point @Sfsx. It's on our roadmap https://github.com/CoplayDev/unity-mcp/wiki/Project-Roadmap, we want to support hosting the server remotely. Will keep this ticket open to track it

[msanatan]

I think HTTP and being able to start and stop the server in the plugin would work around the Codex issues on Windows as well @Scriptwonder - and it's still the last best thing we can do for the asset store haha. I'll have a go at implementing it this upcoming week