[VOTE] Support Stateful Sessions in a Multi-Worker Environment, Using a Shared Session Store

This was an issue that was highly requested by the community when SSE transport was the only mode that was supported.

Now that fastapi-mcp supports HTTP transport, we wonder if it's still relevant.

I'm opening this issue to collect upvotes and see if the community is interested in such a feature.

Currently, stateful HTTP / SSE will only work per-instance.